FM 5-25 Explosives and Demolitions 1967-

Document Sample
FM 5-25 Explosives and Demolitions 1967- Powered By Docstoc
					                                                            =~.   ~ .....- -.:=-~""-_.-_._-~~-~'----~--
                                     -   --_.-----------

  o E PAR                 T MEN T 0 F THE                         ARM Y FIE L D MAN U AL


~RSEDED                  8y      Sqmt?-      !t),                                                           SUPERSEDED
                         )J7J)    $'T~ ~

 HEADQUARTERS,                                      DEPARTMENT                                  OF        THE   ARMY
                                                    .MAY      1967
  TACO   '7258A      .

                  MORRIS S\~
                  USAFAS SNOW HAll
              FORt SILL; OKLA.' 73503
                                                                                                                                                                                   *FM 5-25

                    FIEW MANUAL                     {                                                                                           HEADQUARTERS
                                                                                                                                       DEPARTMENT       OF THE ARMY
                    No. 5-25                        j                                                                                  'VASIIINGTON, D.C. 26 JJfay 1967

                                                                              EXPLOSIVES AND                             DEMOLITIONS

                                                                                                                                                            ParalCrRph   PlllCe

I                                         CHAPTER 1.

                                          Section               I.

                                                                                                                                                              1-3              3

                                                           II.        Military explosive"            and
                                                                        special charges                            ~__ ----------      ------.---             4-28             3

                                                          III.        Demoliton       accessories                                                             29-41        22

                                          CHAPTER 2.                  FIRING       SYSTEMS
                                          Section               I.    Nonelectric       firing       system                                                   42-50        53
                                                           II.        Electric     firing system                                                              51-62        GO
                                                          III.        Detonating       cord priming                                   ---------               63-71        71
                                                          IV.         Dual firing systems                                      .     ----------               72-75        79

                                          CHAPTER 3.                  CALCULATION                AND PLACEMENT                       OF
                                          Section              I.    Introduction                                                                             76-77        85

                                                           II.       Timber       cutting     charges                                                         78-79        85

                                                         III.        Steel-cutting       charges                                                              80-83        87

                                                          IV.        Pressure      charges       _                                        __                  84-85       95

                                                           V.        Breaching        charges                                                                86-87        97

                                                         VI.         Cratering       and ditching            charges                                         88-94        99

                                                        VII.         Land clearing          and quarrying
                                                                       charges                                                                               95-99       106

I                                         CHAPTER 4.
                                          Section           I.
                                                                     Demolition       plan

                                                                     Techniques common to most
                                                                                                              .~                                             100-102     109

                                                                       demolitions                                                                ---        103-105     122

                                                         III.        Bridge      demolitions         __ --                                        - --       106-126     123

                                                         IV.         Damaging        transportation           lines                                     -    121-126     141

                                                          V.         Damaging       communications              s~'stems                           ....      127-128     145
                                                         VI.         Destruction of buildings
                                                                       and installations                     .. - --- __ . __-             ... __ .          129-132     146

                                                        VII.         Destruction      of equipment             and supplies         - -. __ --___            133-137     147

                       .This     manual    supersedes           FM 5-25,   29 October        1963.

;..             . ACoO. 72!iRA

. .....   ...

  UERS~ED                                 __~r
     CHAPTER 5.          SAFE HANDLING, TRANSPORTATION,                              Paragraph    Page
                           AND STORAGE OF EXPLOSIVES
     Section        Y.   General   .arety   precautions   ----________________          138-140    149

               II.       Transportation,    storage, and disposal                       141-145    150

    ApPENDIX A.          REFERENCES                                              _
               B.        METRIC     CHARGE       CALCULATIONS                    _
               C.        USE OF LAND MINES, AERIAL                                                 154
                           BOMBS, AND SHELLS AS
                          DEMOLITION   CHARGES                                   _
               D.        SUl\IMARY OF EXPLOSIVE                                                   157
                           CALCULATION  FORMULAS                             _
               E.        POWER REQUIREMENTS      FOR                                              160
                           SERIES FIRING CIRCUIT                             _
               F.        SPECIAL DEMOLITION           MATERIALS                                   162
                           AND TECHNIQUES                                    _
    INDEX                                                                                         166

                                                                                                         AGO 7258A
                                                  CHAPTER 1

                                          DEMOLITION         MATERIALS

                                           Section I.     INTRODUCTION

  1. Purpose and Scope                                       2. Comments
    a. This manual is a guide      in the use of explo-         Users of this manual are encouraged to sub-
 sives in the destruction of        military obstacles,      mit comments or recommendations          for im-
 and in certain construction       projects.  The ma-        provement. Commends should be referenced to
 terial includes information       on-.                      the specific page, paragraph, and line of text.
                                                             The reasons should be given for ~ach to insure
        (1) Types, characteristics,     and uses of ex-      proper understanding     and evaluation.    Com-
            plosives and auxiliary      equipment.           ments should be forwarded directly to the Com-
        (2) Preparation,   placement,    and firing of       mandant, U. S. Army Engineer School, Fort
            charges.                                         Belvoir, Virginia, 22060.
        (3) Charge   calculation    formulas.               3. Military Demolitions
       (4) Deliberate    and   hasty   demolition              Military demolitions are the destruction by
           methods for use in the forward zone.             fire, water, explosive, and mechanical or other
       (5) Safety precautions.                              means of areas, structures, facilities, or ma-
                                                            terials to accomplish a military objective. They
        (6) Handling, transportation,      and storage      have offensive and defensive uses: for example,
            of explosives.
                                                            the removal of enemy barriers to facilitate the
   b. The contents of this manual are applicable            advance and the construction         of friendly
to nUclear and nonnuclear warfare.                          barriers to delay or restrict enemy movement.


4. Definitions                                              explosive to a gaseous state-detonation--oc-
   a. Explosives.     Explosives are substances             curs almost      instantaneously    (from  1,000
that, through       chemical reaction     violently         meters per second (3,280 feet) to 8,500 meters
ch ange and release pressure and heat' equally in           per second (27,888 feet), producing a shatter-
all d.irections. Explosives are classified as low           ing effect upon the target.      High explosives
or hIgh according to the detonating velocity or             are used where this shattering effect is re-
speed (in feet per second) at which this change             quired-in   certain demolition charges and in
takes place and other pertinent characteristics.            charges in mines, shells, and bombs.
   b. Low Explosives.        Low explosives de-                 d. Relative Effectiveness Factor. Explosives
flagrate or change from a solid to a gaseous                 vary not only in detonating rate or velocity
state relatively slowly over a sustained period              (feet per second), but also in other character-
 (u~ to 400 meters or 1312 feet per second).                istics, such as density and heat production, that
ThIs characteristic    makes low explosives ideal           determine their effectiveness. They vary so
where pushing or shoving effect is required.                much that the amount of explosive used is com-
Examples are smokeless and black powders.                   puted according to a relative effectiveness fac-
   c. High Explosives.    The change in this type           tor, based on the effectiveness of all high explo-

AGO   725BA                                                                                                 3
            ,                                            .
     sives in relation to that of TNT. For example,
     TNT, with a detonating velocity of 23,000 feet                                     f. Positive       detonation          by easily' prepared
     per second, has a relative effectiveness factor of
     1, while tetrytol, with the same velocity, has a                                   g. Suitability for use under water.
     higher relative effectiveness factor of 1.20                                       h. Convenient size and shape for packaging,
     (table VIII).                                                                   storage, distribution, and handling by troops.
                                                                                        i. Capability of functioning   over a wide
     S. Characteristics  of Military Explosives                                      range of temperatures.
        Explosives used in military operations have
     certain properties or characteristics  essential                                6. Selection        of Explosives
     to their function. These are-                                                      The explosives for a particular purpose gen-
       a. Relative insensitivity          to shock or friction.                      eralJy are selected on the basis of velocity of
      b. Detonating            velocity, adequate for the pur-                       detonation.   For example, an explosive having
    pose.                                                                           a high detonating velocity generally is used
                                                                                    for cutting and breaching; that of a lower
       c. High power per unit of weight.
                                                                                    velocity, for cratering, ditching, and quarrying.
       d. High density (weight per unit of volume).                                 The types of explosives commonly used are de-
       e. Stability adequate to retain usefulness for                               scribed below.
    a reasonable time when stored in any climate
    at temperatures between -80 F and + 165 F.      0
                                                                                    7. TNT (Trinitrotoluene)
                                                                                      a. Characteristics (fig. 1).

                Caae                    Color
    Cardboard                J,4
                              Ib-OD                                                                                               Detonating
                                                                          1                                                        velocity
      with                                                % Ib-D 1 h in, L 3% in; % 1h-3% x 1%
                             % Ib-yellow
                           OD 1 Ib-OD
                                                           x 1  *in; 1 Ib-7 x 1   x 1% in.      *                                23,000 fps

     cap well.

           Relative                    Wat ..r
      .. lTectiv ..n....           rt'lliatancc.o                    Low
                                                                t .. mpfOrature
            1.0            Excellent (does not
                                                         Less sensitive to shock.
                             readily absorb                                                     % 1b-200 blocks in wooden box;' %
                             water) •                                                                                               Ib-10O
                                                                                                . blocks in WOOdenbox' lib-50  or 56 blocks
                                                                                                  in WOOdenbox.'                       .

    b. Use. TNT is used in cutting and breach-
 ing and as a main or booster charge for general                                  TNT should attempt this.
 demolition purposes in combat areas. To form                                     If allowed to boil or crystaJlize, it becomes
a charge to fit special targets, it is removed                                    supersensitive and detonates at a small amount
from the package and melted in a double boiler.                                   of shock or exposure to flame.
Then it must be immediately cast in the shape                                        c. Detonation. TNT may be detonated by
needed, because TNT, when melted, becomes                                         military electric and nonelectric blasting caps.
fluid and hardens quickly.
                                                                                  8. Tetrytol
   Caution: Only those who are well-informed
on the characteristics  and reaction of molten                                      a.   },[1   Chain Demolition Block.
                                                                                         (I)    Characteristics (fig. 2).
                                                                                                                                         AGO 725aA
                                                112.LB BLOCK


                                    Figure     1. TNT blocks.

               Case         Color            Size               Wehcht    Dt.-tonRtinlC      RelRlive

A sphal t-impregna    ted   on       11 x 2 x 2 in              21h lb

                                                                         23,000 fps

  paper wrapper.
ACO   721i8A
        2 FT                             BLOCK            WEIGHT
                                                 21 LB

                          /'                                                                                   Figure   3.     M2 demolition              block.

              2 FT
                                                 HAVERSACK PACKAGE
                                                 CONTAINING 8 BLOCKS

                   Figure        f.      Mt chain demolition            block.
               Wal~r      n... lslanee
                                                          Low l~mPt'ralure       e~E'('t.
    Excellent    (only             slightly        Less   sensitive to shock
                                                                                                                                                  Pael<a!l'inj;C               -
      soluble) •                                                              and
                                                     slight decrease in strength.             Tetryl pellet cast             Blocks   are cast 8 in apart                       -
                                                     Cut ends of detonating cord                into block near
                                                                                                each end.                      detonating cord, with 24 in left
                                                     should be waterproofed
                                                                                to                                             free at each end of chain (total
                                                     prevent penetration by
                                                                                                                               192 in). One chain (8 blocks)
                                                                                                                              packed in OD haversack, 11 x
                                                                                                                              8 x 4 in weighing 20.2 lb and
                                                                                                                              two chains in haversacks in a
                                                                                                                              wooden box.
           (2)       Use.  The 1J1l chain demolition block
                     may be used as an alternate to TNT.                                               being eliminated. When present stocks
                    The complete chain, or any part of the                                             are eXhausted, no more will be pro-
                    chain, may be laid out in a line,                                                  cured.
                    wrapped around a target, or used in                                          (3) Detonation.      Tetrytol is detonated by
                    the haversack as it is packed. The                                                .'l1eans of the military electric or non-
                   entire chain will detonate, even though                                           electric blasting cap. The explosive
                   the blocks may not be in contact with                                             end of the cap should extend toward
                   each other. If less than eight blocks                                             the charge.
                   are needed, the required number is
                   cut from the chain. Tetrytol is now                                        b. j/2.Demolition               Block.

                                                                                                (1) Characteristics                   (fig. 3).
Asphalt.impr('gnated                                                                                                            Wclll'ht                     D,.tonnflnll'
                     paper                          wrapper.       Has                 OD                                                                      v~loeity
  threaded cap well.                                                                           11 x 2 x 2 in.
                                                                                                                               21h lb.                     23,000 fps
     .rrl't"t1v"nl"llll                              Watl."r mistanee

                                                                                                                  Low templ."ralure        etTl.'Cts
         1.20                         Excellent      (only     slightly      soluble).
                                                                                            SliR'ht decrease in strength    and less sensitive to
                                                                                               shock. Requires G turns of detonating     cord for
                                                                                              positive detonation;  will explode or ignite under
                                                                                              50-calibre incendiary machine gun fire at subzero

                                                                                                                                                                   AGO 725RA
                                            Booster                                                                            PackalCinlC

    Tetryl pellet cast in block surrounds                       cap well.                      Eight blocks packed in a haversack, weighing approxi-
                                                                                                 mately 22 lb, and two haversacks in a wooden box.

         (2) U.~e. The 1\12demolition block is used
              in the same manner as the :M1 block.
             Tetrytol, however, is now being elimi-
             nated. No more will be issued after
             present stocks are exhausted.
         (3) Detonation.    The 1\12demolition block
             may be detonated by the military elec-
             tric or nonelectric blasting cap.

    9. Composition                C3 (M3 or MS Demolition
      a. Characteristics                (fig. 4).


                                                                                                           Figure    4.    1'113and 1'115demolition        blocks.

 -                            Case                                                             Color                          Explosive                        Size

         Cardboard         wrapper    perforated     for                M3-0D            M5-clear        plastic          Yellow     odorous.
     easy opening;          M5-plastic     container                                                                                               M3-11 x 2 x 2 in
     with threaded         cap well.                                                                                                               M5-12 x 2 x 2 in
-                WcilCht                                                         Relative                                    Water    resistance
                                                       velocity               e"'pctivl'ness
               lb M5-2%                                                                            Good, but must be in container                  to prevent         erosion.
-                                     lb.         25,018 fps                      1.34

-             Low tt'mperatllre

When chilled, color changes to red;
                                     effects                        Boost'r                            PackalCinj(

                                                                                      M3-8 blocks packed in haver-

                                                                                                                                     More sensitive than TNT to
 below -20°F        becomes stiff and                                                  sack and two haversacks in                     initiation by impact; and
 ~rittle; plasticity restored by heat-                                                 wooden box. M5-1      charge                   odorous.
 mg. Velocity reduced at -20°F                                                         in polyethylene bag, 24 bags

 but still of high order.                                                              in wooden box.

   b. Use. Because of its plasticity and high                                                      c. Detonation. Composition C3 may be deto-
de~onation velocity, composition C3 is ideally                                                  nated by the military electric or nonelectric
sUIted to cutting steel structural members.   It                                                blasting cap.
may be easily molded in close contact to irreg-
ularly shaped objects and is an excellent un-                                                   10. Composition C4
derwater charge if enclosed in a container to                                                     a. J!5Al Demolition Block.
prevent erosion.                                                                                     (1) Characteristics (fig. 5).

AGO   72G8A

       Plastic          with threaded         recess
                                                                                                                          color                                   Size                -
                                                                          Clear     plastic
                                                                                                                                                          11% x 2 x 2 in
                    Weohcht                         J>t.tonatin~

                  2% lb

                                                  26,379 Ips
                                                                                                                                    Water    resistance
                                                                                                        Excellent,       if enclosed
                                                                                                                                        in original or improvised
                                                                                                          tainer       to prevent    erosion by stream currents.
                         l..ow u-mPt'rature   ~treet.
      Remains like putty at -70. to                                                                                                                          Remarks'
         +170.F. Below -70" it becomes
        hard and brittle.
                                                                                              One charge packed in polyethy_
                                                                                                lene bag and 24 bags in
                                                                                                                                             C4 is more powerful than                -
                                                                                               Wooden box.                                     TNT, without the odor of
                                                                                                                                               C3. It is now classified
                                                                                                                                              standard   B, to be re-
                                                                                                                                              placed by the M112
                                                                                                                                              demolition charge.

              (2)  Use. Because of its high detonation
                  velocity and its plasticity,   Composi-                                               b.     },!112 Demolition              Cha~ge.
                  tion C4 is well suited for cutting steel                                                   (1) Characteristics              (f,g. 5).
                  and timber and breaching concrete.
              (3) Detonation.   Composition C4 may be
                  detonated by a military electric or
                  nonelectric blasting cap.

               Callt'                     Color     
                                                                color                        Size
                                                                                                                                     D,-tonal in!(
    Plastic     wrapper                  White                                                                                         velocity
                                                              White             11 x 2 x 1 in                                                                   effeetlveness
                                                                                                               1 1,4   lb           26,379 fps                         1.34

               \Valt'r     r~l.lanl"e
                                                         l..ow tl!'mperature    t'ff..-eta
    Excellent it inclosed in                        Remains like putty
                                                                                                             . PadaltinlC
                                                                          at                                                                              R ..mnrkll
       original or impro,:ised                                                                      30 blocks per box
                                                       -70.F  to + 170"F. Be-                                          14 x              This is the standard
       container to prevent                                                                           11% x 819/32 in; total                                       C4
                                                      low .-70. becomes hard                                                               charge replacing the
       erosion by stream cur-                        and brittle.                                     weight 48 lb.
      rents.                                                                                                                               M5A1 block. Sixteen
                                                                                                                                          blocks will be available in
                                                                                                                                          the M37 demolition kit.

         (2)       Use. Because of its high detonating
                  velocity and plasticity, the ~f112 demo-                                               (3) Detonation.   The Ml12 demolition
                  lition charge (C4) is used for cutting                                                     charge may be detonated by a mili-
                  steel and timber and breaching con-                                                        tary electric or nonelectric blasting
                  crete. It has an adhesive compound                                                         cap.
                  on one face for attachment to target.
                                                                                                                                                                       AGO 725RA
  11. M 118 Demolition Charge
    a. Characteristics (fig. 5).
            Calll!                   Color         Explosive                       Size                           Weiltht               Dt'tonatinlt
  -                                                  roJor                                                                               v<'IOI'lty
  Mylar container                   White        Dark     green        Block: 12% x 3~ x 1~                   Block:    2 lb          23,616 fps
                                                                          in Sheet: 12 x 3 x ~ in.            Sheet:    lh lb
                       etrt'CtiVt'neKS            Water   resistance             Low temperatures      effl"CU!                 Parka~inlt
                   effectiveness             Unaffected by                    Retains flexibility at                Four sheets per package
      factor has not yet been                  submersion.                       -6soF;   does not craze              and 20 packages per box,
      established.    For com-                                                  or melt at + 160°F.                   with a volume of 1.1 eu
      puting test shots,                                                                                              ft. Total weight 52 lb.
      use 1.00.
   Remarks. May be cut with a knife and placed in an open fire where it will burn but not explode. Will withstand
 impact of .30 ea!. bullets fired from a distance of 40 ft. Each sheet has an adhesive ,compound on one face.
    b. Use. After the protective cover-strip is
 pulIed off, the sheet of explosive may be quickly
 pressed against any dry surface at a tempera-
 ture higher than 32" F. A supplementary ad-
 hesive has been developed for colder, wet, or
 underwater     targets.    The explosive may be
 used in bulk or cut to accurate width and uni-
 form thickness.      It is particularly suitable for
 cutting steel and breaching.
    c. Detonation.      The MIlS sheet explosive
 may be detonated by a military electric or non-
 electric blasting cap.
 12. Composition    B
   This is a high explosive made of RDX and
TNT with a relative effectiveness factor higher
than that of TNT (1.35), but is more sensitive.
Because of its shattering power and high rate
of detonation, Composition B is used as the
main charge in certain models of bangalore
!orpedoes and shaped charges.      For further
Information see table VIII.
 13. PETN (Pentaerythritetranitrate)
   PETN, the explosive used in detonating cord,
is one of the most powerful military explosives,                               Figure     5.   M5Al,    Mll!,     and M1l8 demolition            blocks.
almost equal in force to nitroglycerine       and
                                                                              highly sensitive and brisant (great shattering
RDX. When used in detonating cord, PETN
                                                                              effect) and the most powerful military ex-
has a detonation velocity of 24,000 feet per
second and is relatively insensitive to friction
and shock. For further information see table                                   16. Pentolite
VIII.                                                                             Pentolite is a combination of PETN and TNT
                                                                              used in the M2A3 shaped charge. Like Compo-
 14. Amatol
                                                                              sition B it has a high rate of detonation and
   Amatol is a mixture of ammonium nitrate                                    great shattering power.
and TNT with a relative effectiveness of 1.17.
                                                                               17. Ednatol
Amatol (80/20) may be found in the bangalore
                                                                                 This is a mixture of halite, or explosive H,
torpedo (table VIII).
                                                                              and TNT. It has no tendency to combine with
15. RDX (Cyclonite)                                                           metals in the absence of moisture, and has no
   nDX is the base charge in the M6 and :M7                                   toxic effects. It is u8ed in shaped charges and
electric and nonelectric blasting caps. It is                                 high explosive shells.
AGO 72liM
     18. Military Dynamite,                                M1
      a. Characteristics                         (fig. 6).
                                                                                                                                      1)~lonating              Relative
  Cartridge        of waxed paper                             Tan                                                                       velocity            effectiveness
                                                                                  8 x 1% in                      ~ lb
                                                                                                                                  20,000 fps                    0.92
       rl'llilllnnce                                        Pacl.aging
                           A-50 sticks in waterproofing                        bag, 2 bags
                             in wooden box                                                               Contains no nitroglycerine    and thus safer to store,
                           B-65 sticks in a carton and 2 cartons                                in         handle, and transport    than commercial dynamite.
                             wooden box                                                                    Unaffected by low temperatures.

    b. Use. Very satisfactory for construction,
 quarrying, and many types of demolition work.                                                        monia-gelatin.   Straight dynamites are named
    c. Detonation.   l\Iilitary dynamite may be                                                       according to the percentage of weight of nitro-
 detonated by means of a military electric or                                                        glycerine they contain; for example, 40 percent
 nonelectric blasting cap, and detonating cord                                                       straight dynamite contains 40 percent nitro-,
 (fig. 79).                                                                                          glycerine.     Ammonia dynamite is different,
                                                                                                     however, as 40 percent ammonia dynamite in-
                                                                                                     dicates that the dynamite is equivalent to 40
                                                                                                     percent straight dynamite but not that it con-
                                                                                                     tains 40 percent nitroglycerine by weight.
                                                                                                            (1) Gelatin dynamite is a plastic dynamite
                                                                                                                with an explosive base of nitrocotton
                                                                                                                dissolved in nitroglycerine and is rela-
                                                                                                                tively insoluble in water.         '
                                                                                                            (2) Ammonia-gelatin dynamite is a plastic
                       Figure     6.          Military     dynamite.                                            dynamite with an explosive base of
 19. Commercial                       Dynamites                                                                 nitrocotton dissolved in nitroglycerine
                                                                                                                with ammonium nitrate added. It is
  a. Introduction.                       Commercial types of dyna-                                              suitable for underwater use.
mite are straight,                      ammonia, gelatin, and am-
                                                                                                         b. Characteristics.
Paraffin-treated           paper                   Tan                                                                                Composition
                                                                      8 x 11.4 in                1h lb
                                                                                                                Straight-nitroglycerine         and nonexplosive
                                                                                                                  filler. Ammonia-ammonium               nitrate and
                                                                                                                  nitroglycerine.      Gelatin-nitrocotton      dis-
                                                                                                                  solved in nitroglycerine.        Ammonia-gelatin
                                                                                                                  -same      as gela'tin with ammonium nitrate
               J)t'lonnllnlC    Vtol()("lly
                                                                            R40r"th'p .trt'('lIvpnPll8
Straight                40 ~~-15,000               Ips                                                                                 Water   resistance
                        50 %-18,000                fps                                                                   Good if fired within 24 hours
                        60 '1~-19,000              fps
Ammonia                 40 '1t- 8,900 fps
                        50 %-11,000   Ips                                                                                 Poor
                        60 %-12,000 fps
Gelatin                 40 '1~- 7,900 fps
                        50 %- 8,900 fps                                              0.47
                        60 '1~-16,000 fps                                                                                 Good
Ammonia-                40 %-16,000                fps
 gelatin                50 %-18,700                Ips
                                                                                                                                                              AGO 72MlA

 . Requires    careful handling,    as flames, sparks, friction, and sharp blows may cause detonation,   and special care
 In storage,   as it deteriorates   rapidly. It is thus undesirable for military use.

    c. Uses. Being sensitive to shock and fric-                             gallon container may be combined to
 tion, commercial dynamite is not generally                                 make a good substitute.
 Used in forward areas; but it is acceptable in                          (a) Heat water in a separate container
 emergencies when other more suitable ex-                                      to a temperature as high as can be
 plosives are lacking.    Sixty percent straight                               tolerated by the hand.
 dynamite, of less strength than TNT, has a                              (b) Pour the heated water into the
variety of uses; gelatin dynamite is applicable                                water compartment of the thawing
to underwater demolitions and to land clearing,                                kettle (10 gallon can).
cratering, and quarrying.     A gelatin dynamite                         (c) Lay the frozen dynamite in the in-
of low heaving force and a high rate of detona-                                ner compartment       (5-gallon con-
tion is used for blasting hard rock.                                           tainer)   in' a horizontal position,
   d. Detonation.    Commercial dynamites may                                 with the bottom sticks supported on
be exploded when primed with a commercial                                     strips of wood or other material, so
NO.6 or larger, blasting cap, a military electric                              that the air can circulate readily
or nonelectric blasting cap, or detonating cord                               arou'nd the sticks.
(fig. 79).                                                              (d) Place the kettle in a barrel or box
                                                                              insulated by hay or some other sat-
   e. Low Temperature      Effects.  The sensi-                               isfactory material.
tivity of dynamite decreases at diminishing
                                                                        (e) Thaw no more than 50 pounds of
temperatures until the dynamite freezes, after
                                                                              frozen dynamite in a single lot.
which it becomes extremely sensitive.    Gelatin
dynamite does not freeze as easily as straight                          (f) Never place the frozen dynamite in
dynamite.    When straight dynamite is stored,                                the thawing compartment         of the
the nitroglycerine   tends to settle out of the                               kettle before the hot water is poured
sticks; accordingly, straight dynamite cases'                                 into the water compartment.
should be frequently and regularly turned until                         (g) Never set the kettle over heat after
freezing sets in. Frozen dynamite may be                                      the dynamite has been placed in it.
thawed in a kettle as described in g, below.                         (2) Frozen dynamite is completely thawed
  f. Old Dynamite.      Old dynamite may be rec-                         when it has returned to its original
ognized by the oily substance collected on the                           consistency.   This can be determined
casing or by stains appearing on the wooden                              by squeezing the sticks lightly with
p.acking case. These are caused by the separa-                           thumb and forefinger.     If no hard
tIon of the nitroglycerine from the porous base.                         spots remain and when unwrapped no
~ynamite in this state, being extremely sensi-                           crystals are seen, it is thawed and
tive, must not be used but destroyed immedi-                             ready for use.
ately by burning (Tl\I 9-1300-206).
                                                                20. Foreign Explosives
   g. Frozen Dynamite.     Frozen dynamite is                     a. Types. Explosives used by foreign coun-
recognized by its hardness and by the appear-                  tries include TNT, picric acid, and guncotton.
ance of crystals (which are extremely sensitive)               Picric acid has characteristics like TNT except
in the contents of the stick.     Its use is not               that it corrodes metals and thus forms ex-
~ecommended. It may be destroyed by burning                    tremely sensitive compounds.       A picric acid
In the same manner as old dynamite.       Frozen               explosive in a rusted or corroded container must
dynamite, may be used, however, if thawed as                   not be used; in fact, it should not be handled in
follows:                                                       any way, except to move it very carefull)' tv a
      (1) Use a commercial thawing kettle. If                  safe disposal area or location for destruction
          this is not available, a 5- and a 10-                (app C).
AGO 725M
     b. Uses. Explosives of allied nations and
  those captured from the enemy may be used to
  supplement standard supplies. Such explosives,
  however, should be used only by experienced
  soldiers and then only according to instructions
  and directives issued by theater commanders.
  Captured bombs, propellants, and other devices
  may be used with U. S. military explosives for
  larger demolition projects, such as pier, bridge,
 tunnel, and airfield destruction (app C). 1\10st
 foreign explosive blocks have cap wells large
 enough to receive U. S. military blasting caps.
 These blasting caps, when used to detonate
 foreign explosives, should be test fired to de.
 termine their adequacy before extensive use.                                      AMMONIUM            NITRATE

 21. Ammonium Nitrate
     a. Characteristics   (fig. 7).                                                 RING FOR





                                                              Figure     'l.   Ammonium        nitrate and nitra,mon cratering
                                                            We!ltht. of charl('e
Cylindrical     metal                                                                Detonating-   velocity     Relative      effectiveness
                                          17 x 8% in
                                                                11,000 fps
                                                                                              40 lb                        0.42

Poor. Should not be removed from con-                                                                         Booster
  tainer in cratering because of moist-   Slight loss in strength    but functions
                                             satisfactorily.                               TNT        surrounding       the     cap    well.
  ure absorption.

One charge is packed in wooden box 22 % x 9 % x
  9   in. Total wt 50.8 lb.                                Container  has ring
                                                             into boreholes.
                                                                                       on top for         handling      and      lowering

   b. Uses. Having a low detonating velocity
 (11,000 fps) and thus a low shattering power                monium nitrate is used chiefly as a cratering
that produces a pushing or heaving effect, am-               charge. It is also effective in ditching.
                                                               c. Detonation.  The container has a cap well
                                                                                                                               AGO 72liRA
and a detonating cord tunnel for priming.      A
cleat is placed above and to the side of the cap
well for attaching electric and nonelectric. pri-
mers. Frequently a primed one-pound block of
TNT is placed on the charge to insure detona-

 22. Nitramon Cratering Charge
   a. Characteristics (fig. 7).
           Container                         Color                        Size

 CYlindrical.          metal.                on                      24 x 7 in

 Well{ht   of charge            Detonatink    velocity         Relative    effectiveness

       40 lb                       11,000 fps                             0.42

               Water     resistance

Poor.    Should not be removed
  from the metal container      in
  cratering   because of moisture


    TNT surrounding                   One metal container in wooden
      the cap well.                     box 27% x 8% x 9% in.
                                        Total weight 52 lb.                                                                            15t IN

   b. Use.    Because of the low detonating
velocity (11,000 fps) and low shattering power
that produces a heaving effect, this charge is
very effective in cratering and ditching.    The
container has a ring on top for general handling
and lowering into boreholes.
   c. Detonation.   The container is fitted with
a cap well and a tunnel for priming and a cleat
to attach electric and nonelectric primers.    A
primed 1.pound block of TNT is placed on the
charge for positive detonation.


                                                                                           ,-                 91N                 ~I
                                                                                                Figur~   8.   Shaped   chargeR.

     23. Shaped Charges
                                                                                                recess, and a metal or glass liner. in the. base.l
        A shaped charge is an explosive charge 'with
                                                                                                The threaded cap well in the top is for priming .
     its detonating action directed to increase its
                                                                                                with military electric or nonelectric blasting ~
     effectiveness In penetrating steel, armor, and
                                                                                                caps     Shaped charges, generally, are made '
     concrete and other masonry (fig. 8). Charges,
                                                                                                from such explosives as Composition B, pento-
     as issued, are usually cylindrical in shape but                                            lite, and ednatoJ.
     may be linear like the charges included in the
     :M157 demolition kit (para 27c). Cylindrical
                                                                                                     a. M2A3 and M2A4 Shaped Charges.
     shaped charges have a conical top, a conical
                                                                                                         (1) Characteristics               (fig. 8).

                   Cau                            Color
  'Vater        resistant     fiber                OD
                                                                      Wehcht of charge
                                                                                                                          Explosive                        Boollter
                                                                           12 lb
                                                                                           14 15/16 x 7 in          50/50 pentolite          M2A3:    50/50 pento-
                                                                                                                      or composi-              lite with comp B
                                                                                                                      tion B.                 explosive.
                                                                                                                                             M2A4: Comp A3, re-
                                            I                                                                                                 sistant   to small
                                                                                                                                              arms fire.

          LIner               Low     ~mperatu~           l'trecta
         Glass              Satisfactory          in arctic                                                                                  RemarkJI
                                                                      Three charges    packed in Wooden
                              climates.                                                                                 Both model~ have a cardboard         cy-
                                                                        box 33'At x 10 % x 9 ~ in. Total
                                                                        weight 66 lb.                                     lindrical standoff fitted to the case.

          (2)        Shaped charges are used pri-
              marily to bore holes in earth, metal,                                                          shaped charges contain a threaded cap
              masonry, concrete, and paved and un-                                                           well for detonation by electric and
              paved roads. Their effectiveness de-                                                           nonelectric blasting caps. Dual prim-
             pends largely on their shape and the                                                            ing, however, is extremely difficult be-
             material of which they are made, the                                                           cause of the configuration of the case
             explosive, and proper placement. The                                                           and the need for priming at the exact
             penetrating capabilities in various ma-                                                        rear-center.    They are not effective
             terials and proper standoff distances                                                          under water because of the obstruc-
             are given in table XII.                                                                        tion to the jet.
         (3) Detonation.    The M2A3 and :M2A4                                                      b. },!3 Shaped Charge.
                                                                                                       (1) Characteristics    (fig. 8) ..

                               C~lor               Wehcht of charn
        Metal                   OD                           30 lb                                                                                       Boostt'r
                                                                             15~     x 9 in (less            50/50   pentolite
                                                                                standoff).                                            or    50/50 pentolite  with
                                                                                                               composition B.                 comp B charge.

                                    I..ow   ~mJlf'ratu~

Steel    or      copper        Satisfactory  in                      One each in Wooden box 20 ~ x
                                 arctic climates.                                                                     Provided with metal               tripod      standoff
                                                                       13% x 11% in. Total weight 65 lb.                15 in high.
                                                                                                                                                                 AGO 725M
         (2) _Use. Shaped charges, primarily, are                              of the obstruction              to the jet.'
               used to bore holes in earth, lnetal,                   c. Special Precautions.    In order to achieve
              masonry, pavement and the like., Ef-                .the maximum effectiveness of shaped charges-
              fectiveness depends considerably on                        (1) Center the charge over the target
              the shape and material in the cone,                            point.
              the explosive used, and proper place-
                                                                         (2) Set the axis of the charge in line with
              ment.     The penetrating  effects of
                                                                             the direction of the hole.
              shaped charges in various materials
              and relative standoff distances are                        (3) Use the pedestal provided to obtain
              given in table XII.                                            the proper standoff distance.
         (3) Detonation. The 1\13shaped charge is                        (4) Be certain that there is no obstruction
             provided with a threaded cap well for                           in the cavity liner or between the
             detonation by electric and nonelectric                          charge and the target.
             blasting caps. Dual priming is very                         (5) Be certain that soldiers using shaped
             difficult because of the slope of the                           charges in the open are at least 900
             case and the need for exact rear-cen-                           feet away in defilade under cover, or
             ter priming.    The M3 shaped charge                            at least 300 feet away if in a missile-
             is not effective under water because                            proof shelter, before firing.

 24. M 1A 1 and M 1A2 Bangalore Torpedo Kits
   a. Characteristics (fig. 9).
 -     CliMe     Color                 Component.      Stoction   weill:ht         Se<-tion                         Explollive

 -    Metal      on       10 loading assemblies or    Approx       13 lb

                                                                              5 ft x 2 % in
                                                                                                          MIAl-approx 9 lb amatol
                            sections; 10 connecting                                                        and TNT booster; MIA2
                            sleeves; one nose                                                              -approx  9 lb comp B
                            sleeve.                                                                        and comp A3 booster.
                         PackalCinll                                                            Remarks

 One kit packed in wooden box 64% x 13% x 7% in.           Four inches of length               at both ends of each section con-
   Total weight 176 lb.                                      tains a booster.

      b. Assembly for Use. All sections have a
   threaded cap well at each end so that they may
   be assembled in any order.        The connecting
  sleeves make rigid joints.       A nose sleeve is
  placed on the front of the torpedo to assist in
  PUshing it through entanglements and across
  the ground.     It is also desirable to attach an
  improvised loading section without explosive
  on the end to forestall premature detonation by
  a mine when the torpedo is shoved into place.

  In the assembly of two or more tubes, the nose
  Sleeve is pressed onto one end of one tube, and
  the other end is connected to a second tube by a
. connecting sleeve.      A bangalore torpedo or                                      CONNECTING           SLEEVE
  torpedo section may be improvised by the use
  of a 2-inch diameter pipe with a 24-gage wall
  thickness with approximately 2 pounds of ex-                    ~----------~          LOADING       ASSEMBLY
  plosive per foot of length.       Successive pipe
  lengths, however, must be closely connected.                               Figure    9.   MIAI      bangalore     torpedo.

ACO    72ri8A
            ('. {','('.              Th{. hanga]on'                              t()rpedo        e1 ars            a path
       1() to              1G               wid{.             th rough              barb          d wire              en-
      tanvl('IlH'Ilt..      In min<'fipld    b >aching,   it will
      {' 'plocl(' all antipl'l ..'onn .1 min '.' and mo. t of the
      allt itank              minp.'             in a narrow                      foot      path.                  any         of
      Ow millt ..' at thp .'ide>, ho n'ver                                                may be ~hocked
     into a , PI1. iti\'(, ..tah'.                                        which           mak s extreme
     ca rp IH.C(....'ary   in any                                          further          miner]earing-,
      B;lIwalo!"l'                    torppdop.'                     a]~o           may            b          u~ed             in
     IHlndll'.'              a . .'llh.'titlltt'                   ('xplo.         ivp charg                  s in the                                                ASSfMBLY
     .1:~\ 1 ant itank milwc]paring                                                   proje            t d charge
     cI(' mol it ion kit (f1 r, J:~).

          d. DrfoJ/flfioN.    Thp military   elpctric or non-
     (.I(.(,t ric bla' i IW cap. will detona    e thp bang-a-
     Ion'       to!"J>pdo.    In ob.'ta('11' c!paralH'e,                                                thp banga-
     Ion'       torp('do   , hOllld !>p prim{'d aftpr                                                  i has be n
     plac('<1.              TIll' cap              \\"pll at thp pnd . hould                                  lw pro-
     tl'dt.cI            with         tapl'            or      a \vood{'n                 pIll r whilp                 the
  torppdo     i. lH'ilw pll.'hpd                                            into place.    Priming
  i.' VPIH'rally   clonp pithpr                                            by mpan.     of priming
  adaptpr                   and         a military                      'lpdric             or      nonpl etrie
  bla.'tinv                 ('ap        and timp                     fll.p, or              by      d{.tona ing
  cord with.   i. turn.   around                                                   thp      1-inrh            boo.     tel'
  portion  of thp torp{'do.

  25, M37                       Demolition                          Charge               Assembly
      Thp     1:n chaq!(' a .'('mbl)' (fiV. 10) <'onsi. t
  of ('ivht    .1,; \ 1 dl'molition  b!ock~, piS!h demo-
  lition    block    !look a' prnblip',    and  two     Hi
  pri m i IlV a.'.'1'1ll hI ip.,                               1 hp dl'mol ition                       block~         arp
 pack('d                   in t      '0      b:w             , fOllr         blo('k           I)(>r b.        v,     and
                                                                                                                                               Figure     JO.   M, 7 demolition     chfl'r,gc   assembly.
 Ow a ':~('mbl.\' pl:ll'pd in an . HG carr 'inv ca. P.
 Thp .11:; pri m i IW a . pm hly i. a !i-foot I{'ngi h
 of dl'tonatilW                            cord with           \\"0 pia. tic                            ad; pter.                    cap or by a ring             main    attached      by means            of the
 and two IU).'                            hr)(l.'t('r.' atta('hpd.      Thp                             adap     r.                  detonating- cord             clips    provided.
 an'        thrl';t<1l'd                to        fit        Uw          . tandard             cap        \ '1'11 in                    c. Packa,qi11.f/.           One <ti-li-lembly is packed             in an
 I nl'      d('lnoli              ion           block.              Thl'          primin           r a.       {'mbly                      5 carrying            ('a~e, and two arc packed                    in a
 ha.' t            0     dt'follat         ilw cord                 clip          for fI inv              h{'.         :37           wooden      box 17'111 xl]             'h x ] 2 ~~ inches,               The
 C'harVt.              a     '!'Illhl\            to         thp        main         lllu'.            Tht'        hook              'ro.':-\ pa('kag-' wPight            ii-l 57 pound:'!.
a '('nllllil"                 an'               hook'           and pil'{'{',                 of        rOI)('       for
att:ll'hilw                 char          r(.      to          hr' tarvt'f.                                                         26.        Rocket-Propelled Train Bangalore
                                                                                                                                                orpedo (Barney Google)
      fl.    (',   'r.          Th i             a .'I'm bl)'               i      appl il':lbh.              to      hp
                                                                                                                                        Th( dt'vice ('on~i~t~ of 20 section~       of banga-
II (.       of a            'allil        d('molit             ion         tpam           in thp              n'duc-
                                                                                                                                    lon'     torp do f1tt'd      together   by Hpecial   con-
I iOIl of (Ib.'tat'll'.                                 It     i        \I'r\'      P f( (' i (. :wain,                    t
                                                                                                                                    lu.{'tin).! HIe 'V'i-l to form     a IOO-foot train  (fig.
.'Illall dra rOil" h'( Ih appro 'imat                                                    ,1.' :~ fp.t              hivh
                                                                                                                                     1]).       J      kit {'ontainH  the ro{'ket        motor,    tail ClIi-
:lnd .~ f(.,.t \\ irll' at ttw ha ('.
                                                                                                                                    . ('mhli        'H, and {'lluplin ri-l for 20        ~ections.      The
    II. 1)( fOJ/ofiol/.          Th( .• 1:ri d('lllOlitiIJll charvp                                                                  motor    iH fittpd to th' froflt             of the train         to pro-
i.' dt'fllllaft.d      1>.\ rlll'all. of th( .. f I:; pr Imirw.     _                                                               \. idp propu IHiofl. J)donation                 occu rH at       the tail
,('mhly            alld         all       (.I(.('triC'             or       flOfll'lt.<'tri('           hI;        tlllg            a .. I'mhly           by meaflH of a nonel >ctric               blasting
                                                                                                                                    (" P. pull          fuz{, and a rcel of cabIc.
                                                                                                                                                                                                   Ano      72fiRA
                               111'~~               ~)f-)..,

                              ./                               -/1
                                           ANCHOR              GROUND
                     FIR~G   DEVICE        CABLE               STAKE

                                  Figure   11. Rocket-propelled         bangalore   torpedo   (Barney   Goog/e).

   a. Uses. The rocket-propelled bangalore tor-                              taken cover, the rocket motor is fired. elec-
 pedo is used against barbed wire entangle-                                  trically. After the torpedo has traveled a dis-
ments, antipersonnel mines, and similar small                                tance equal to the length of the anchored cable,
obstacles. The rocket propulsion enables deeper.                             the pull fuze is actuated and the assembly
penetration    of sman obstacles with less ex-                               detonated.
posure of friendly soldiers to enemy observa-
tion and fire.                                                              27. Proiected Charge Demolition Kits
   b. Detonation.   The assembled torpedo is                                   a. J.[1 and J.[lEl. These are identical in all
placed at a spot within range of the target.                                respects except for the delay detonators and the
The 400-foot reel of cable is shortened to the                              time blasting fuze igniters issued with them.
proper length and its free end is anchored                                  The MIEI has the M60 weatherproof blasting
firmly. After the safety has been unscrewed                                 fuse igniter and the IS-second delay MIA2 per-
from the tail assembly and all soldiers ha~e                                cussion detonator, while the Ml has the M2
AGO    726M
      323-&81 0 • 88 • 2
      weatherproof blasting fuse iiniter and the 15-
      second delay :Ml or ~UA1 friction detonator
      (fig. 12).

            (1) Components.         These are a nylon-cov-
                    ered detonating cable, propulsion unit,
                    launcher, fuse lighter, delay detonator,
                   anchor stake, and carrying case. The
                   explosive item, or detonating cable, is
                    1 inch in diameter and approximately
                   170 feet (52 meters) long; it weighs                                 \    RETAINER
                   63 pounds, 46 pounds of which is oiJ-              TIME   BLASTING   FUSE
                   soaked PETN. The detonating cable
                   is composed of 19 strands of special
                  detonating cord, each containing 100
                  grains of PETN per foot. This differs
                  from the regular (reinforced)        deto-
                  nating cord, which contains only 50 to
                  60 grains of PETN per foot. Regular
                  detonating cord cannot be used as a
                  substitute in the kit.
           (2) Use. This kit is emplaced to project
                 and detonate a cable across a pres-
                 sure-actuated antipersonnel minefield.
                 Grass, leaves, other light vegetation,
                 and some soil are blown aside in a
                 lane about 8 feet wide. ~Iore soil is                  Figure 12.          M1E1 projected   charge kit.
                blasted asiue when the ground is moist
                and soft than when it is dry and hard.            the ~I2, M2A1, M3, and M3A1, consist of 8emi-
                Camouflaged antipersonnel mines and               rigid proj ected charges and the accessories and
                those near the surface in the 8 foot              tools needed to assemble and attach them to a
                lane are usually exposed.
                                                                  Jight or medium tank. They are approximately
          (3) Detonation. One soldier fires the com-              14 inches wide, 5 inches high, and 400 feet
                plete assembly.      First the kit is em-         (121.9 meters) long, weighing approximately
                placed; then the fuse lighter on the             9,000 pounds, inclUding 4,500 pounds of ex-
               jet propulsion unit is pulled. The 15-            plosive. They are supplied in elliptically-shaped
               second delay in the propulsion fuse               units or elements 5 feet long, containing about
               a]]ows the soldier to move the 5-foot             35 Pounds of explosive. The M3 consists of an
               distance from the launcher to the an-             80/20 amatol charge and a 6-inch crystalline
               chor stake and pull the fuse Jighter              TNT booster at each end. The M3A1 (fig. 13
               safety pin and pull ring on the deto-             and table I) consists of Composition B charge
               nating cable (which also has a 15-sec-           with a Composition A-3 booster in each end.
              ond delay) and then take cover at least           Bangalore torpedo explosive elements may be
               100 feet behind the assembly.                    substituted for the standard explosive elements,
         (4) Packaging.        The complete assembly is         four for each. Both are initiated by two bulIet-
              issued in a OD-colored waterproof                 impact fuses by fire from the main tank arma-
              aluminum carrying case. Each case                ment or from any 37mm or larger high
              is packed in a wooden box 25th x                 explosive she]] with a super-quick fuse. Both
              18% x 19Y~ inches. The gross weight              types have a threaded cap well suitable for a
              of the kit and box is 142 pounds.                standard firing device and an electric or non-
     1J. Antitank ft/ine-Clearing Kits. These kits,            electric military blasting cap. This cap we]]
                                                               also makes possible the Use of the explosive ele-
                                                                                                                    AGO 725M
 ment as a separate expedient charge. In most            meters (330 feet) long, 5 meters    (16 fee~)
 soils, these charges form a crater about 100            wide, and 2 meters (7 feet) deep.           "


                                               14   IN

                       TOWING    HOOK

                                           NOSE RETAINER
                                          WELDED TO ADAPTER
       TOWING   HOOK


                                                    BUMPER    RING

                                Figure   13. M3At projected   charge   kit.

AGO   7268A
     _.                Table I.   Comparison    of M2. M2Al. M3~ and M3Al          Projected      Charge    Demolition     Kits
     Total net weight                                                           M2Al
                                   12,500 lb                                                                           M3 and   M3Al
                                                               15,000 lb
     Corrugated    plates                                                                                   9000 lb
                                  Steel, 53 lb, 164
                                                               Steel, 53 lb, 172
     Washers                       1 per bolt, 2 in long                                                   Aluminum,      16 lb, 200
                                                               1 per bolt, 2 in long
     Nose                                                                                                  2 per bolt, 4 in long
                                  Steel, two piece, bolted;    Steel,  two piece, bolted;
                                    held to adapter by                                    held             Aluminum, one piece, welded;
                                    bolt.                        to adapter by special re-
                                                                 tainer.                                     held to adapter by special
     Tampins;:' has;:'s           Paper                                                                      retainer.
     Pu~hjng   nttnchment         Wire rope                                                                Cloth or paper
                                                              Steel chain
     Total explosive              3200 lb                                                                  Steel chain
                                                              4500 lb
 l-~xpl08ive cartridges           4 feet long, 20 lb ex-                                                   4500 lb                         -
                                                              5 feet long,
                                    plosives; steel casing;                 35 lb explosives;              5 feet long, 35 lb explosives;
                                                                aluminum casing;
                                    circular in cross sec-                          elliptical               aluminum casing; elliptical
                                    tion.                       in cross section.
                                                                                                             in cross section.
 Fuze and shield                  1 of each
                                                              2 of each
 Towing assembly                  Rope on towing yoke                                                      2 of each
   rigging.                                                   M2 fittings and
                                    raised by hand.                             rigging im-                M2 fittings and rigging im-
                                                                proved and strengthened;
                                                               cable on towing yoke raised                  proved and strengthened;
                                                               by winch on                                  cable on towing yoke raised
                                                                              periscope fit-                by winch on periscope fit-
                                                                                                                                               _ ..

                            TWO IMPACT          FUZE SECTION
                               LOADING          ASSEMBLIES


                                      JOINT     SYSTEM

                                      Figure    U.    M-151   projected    d'!molition   charge    kit.

                                                                                                                                   AGO 7258A
     c. Jf-157.                                                       bullet impact fuse, which has a target
        (1) Description.       This kit (fig. 14) meas-               plate that bears on the firing pin and
               ures about 12 inches in width, 7 inches                is held in place by a shear pin and
               in height, and 400 feet (121.9 meters)                 a safety fork that must be removed
              in length. It consists of 79 sections                  before the fuse can be actuated. The
              -1 nose section, 13 body sections, 62                  fuse is detonated by fire from the main
              center-loading sections, 2 impact fuse                 tank armament or from any 37mm or
              sections, and 1 tail section. Only 64                  larger high explosive shell with a
              of the 79 sections contain explosives-                 super-quick fuse. Two fuses are pro-
              the 62 center loading sections and the                 vided to insure that one is visible to
           . 2 impact fuse sections.           The kit               the tank gunner at all times.
              weighs 11,000 pounds including ap-
              proximately 3,200 pounds of explosive.       28. Improvised Charges
              The explosive is a linear shaped                Demolition teams operating in the field fre-
              charge, 12 inches wide, 7 inches high,       quently find targets to which standard methods
             and 5 feet long, containing approxi-.         and charges may not apply and improvisations
             mately 45 pounds of Composition B             are required.     Frequently the. success of the
             and 5 pounds of Composition C-4. As           mission depends upon the ingenuity or the
             the insert tubes are welded to the           team. The package and pole charges are such
             walls of the center loading sections,        improvisations.     By skillful modifications they
             the explosive elements cannot be used        may be applied successfully in many situations.
             as separate charges or replaced by any           a. Package Cha.f.ges. Charges prepaored in
             substitute item in the field. The linear     convenient packages of appropriate         size and
             shaped charge insures a wider, clearer       shape are always more readily put in place than
             path throughout minefields than many         other types. Explosives may be packaged in
             other explosive clearing devices. In        sandbags to make elongated cylindrical charges
             most soils this charge forms a crater        for boreholes.     Blocks of TNT or other ex-
             about 100 meters (330 feet) long, 4 to      plosives may be stacked together and bound
             5 meters (12 to 16 feet) wide, and 1 to     with tape or twine or wrapped in canvas, other
             Ith meters (3 to 5 feet) deep.              cloth, or paper. A satchel charge may be im-
       (2) Use.       Projected demolition charges       provised by tying or taping explosive blocks to
            are used chiefly in the deliberate           a board with a handle attached. Large charges
            breaching of minefields. They are also       may consist of an entire case of explosives:
            effective against bands of log posts,        Here at least one block or one cartridge is re-
            steel rail posts, antitank ditches, and      moved from the case, primed, and replaced. A
            small     concrete     obstacles.    These   still larger charge may be made by lashing
            charges are adeql:late to break down         several cases of explosive together.      The deto-
            the sides of an antitank ditch. They         nation of a single primer will fire the entire
            will also clear a path through the ditch    charge. Dual priming systems, however, should
            adequate for tank traffic, if it is un-      be used if possible.
            revetted and 5 feet deep or less and if.         b. Pole Charges.      Pole charges are con-
           the charges project beyond the far           venient for placement against pill boxes, hard-
           side of the ditch. They are effective        to-reach bridge stringers, underwater bridge
           in ditches from 5 to 8 feet deep if the      supports, and other locations not easily accessi-
           soil is very favorable.      The explosive   ble. Pole charges are usually an assembly of
           elements of the 1\13 and 1\13Al pro-         an explosive charge; detonating cord; fuse
           jected charges may be used as expedi-        lighter, time fuse, nonelectric blasting cap; and
           ent individual charges in the 1\1-157        a pole for placing or propping them in position.
           kit.                                         Pole charges are usually prepared in the same
      (3) Detonation. The charges are generally         manner as package charges.           Dual priming
           detonated from a tank by means of            should be used, if possible.
AGO 72li8A
             MORRIS 5Wm
             USAFAS SNOW HALL
             fORT SIU, OKLA.     73503
                                          Section III. DEMOLITION ACCESSORIES

     29. Time Blasting          Fuse
        Time blasting fuse transmits a flame from a           around the outside at I-foot or 18-inch intervals
     match or igniter to a nonelectric blasting cap           and double painted bands at 5-foot or 90-inch
     or other explosive charge, providing a time              intervals, depending on the time of manufac.
     delay wherein blasters may retire to a safe             ture.     These bands are provided for easy
     distance prior to the explosion. There are two          measuring purposes.      The burning rate is ap.
     types: safety fuse and time fuse M700. These            proximately 40 seconds per foot, which permits
     may be used interchangeably.                            the soldrer firing the charge to reach a place
                                                             of safety. The burning rate, however, must al.
      a. Safety Fuse. Safety fuse is limited stand-
                                                             ways be tested in the same manner as that of
   ard. It is used in general demolitions. It con-
                                                             safety fuse, above. At arctic temperatures,
   sists of black powder tightly wrapped with
                                                             the outside covering becomes brittle and cracks
  several layers of fiber and waterproofing ma-              easily.
  terial and may be any color, orange being the
  most common (fig. 15). As the burning rate
  may vary for the same or different rolls from
  30 to 45 seconds per foot under different atmos-
  pheric and climatic conditions (exposure for
  over 12 hours to the elements, extreme changes
  ih temperature, and the like), each roll must
 be tested prior to using in the area where the
 charge is to be placed. Particular precautions
 must be taken if used under water, as the rate
 of burning is increased significantly.    Accord-
 ingly, each roll should be tested under water
 prior to preparation of the charge. In arctic
 temperatures,    the outside covering becomes
 brittle and cracks easily.

                                                                         Figure   16.   Time   fUBe M'ioo.

                                                              c. Packaging.
                                                                 (1) Safety fuse.
                                                                   (a)   50-foot coil, 2 coils per package, and
                                                                         30 packages (3000 feet) in a wooden
                                                                         box 24%, x 15%, x 12~ inches. The
                                                                         total package weight is 71.8 pounds.
                                                                    (b) 50-foot coil, 2 coils per package, 5
                 Figure   15.    Safety   fUBe.                         packages sealed in a metal can, and
                                                                         8 cans (4000 feet) per wooden box
   b. Time Fuse It/roo. This fuse (fig.            16) is               ,30 x 140/8 x 140/8 inches. The total
similar to safety fuse and may be used              inter.               package weight is 93.6 pounds.
changeably with it. The fuse is a dark             green           (c) 50-foot coil, 2 coils per package, and
cord 0.2 inches in diameter with a plastic         cover,               60 packages (6000 feet) per wood-
either smooth or with single painted               bands                en box 29 x 22 x 17 inches. The
                                                                        total package weight is 162 pounds.
                                                                                                             AGO 7258A
             (2) Time fuse !tI700. This is packed in
                 50-foot coils, 2 coils per package, 5
                 packages per sealed container,- and 8
                 containers   (4000 feet) per wooden
                 box 30th x 15th x 14'Vs inches. The
                 total package weight is 94 pounds.
  30. Detonating                 Cord
    a. Characteristics. Detonating cord consists
  of a core of PETN in a textile tube coated
  with a layer of asphalt.    On top of this is an
  outer textile cover finished with a wax gum
  composition or plastic coating (fig. 17). It
 will transmit a detonating wave from one point
 to another at a rate of at least 5900 meters per
 second or about 19400 feet.        Partially sub-
 merged water-soaked detonating cord will de-'                                                                                    EXP.LOSIVE
 tonate if initiated from a dry end. Although                                                                                      (PETN)
 it does not lose its explosive properties by ex-
                                                                                               RAYON                          SEAMLESS
 posure to low temperatures,     the covering, be-
                                                                                               LAYER                          COTTON TUBE
 coming stiff, cracks when bent. Thus great
 care is required in using detonating cord prim-
 ers in arctic conditions.     Data on the types
 available is shown in table II.

                                                                                  Figure      11.      Reinforced      pliofilm-wrappcd             detonating
                                                         Table II.   Detonating      Cord Data
                           Nom.                                                                                     Packlmc
       Nunll'nclftture   dift. (in.)       ('-ovcrinlC         LoauinlC
                                                                                                                      Dimension    (inche1l)            WpilCht
                                                                                     o.... crilltion                                                     (lhs.)
                                                                                                               lA'nlCth       Width       Ih'i~ht
CORD, DETO-                0.210       Cotton with         50 grn            1. 1,000 ft/spool,                 10%           10               10           16
  NATING:                                wax gum             PETN/ft.            1 spool 0,000
 fuse, prima-                            composition                            ft)/wdn    bx
 cord (PETN)                             finish.                             2. 100 ft/spool,                   19%           18%              81h         46
  Type 1••                                                                      25 spool (2,500
                                                                                ft)/wdn    bx
                                                                             3. 500 ft/spool, 1                30             15               14%        105
                                                                                spool/sealed can,
                                                                                8 can (4,000
                                                                                ft)/wdn bx

I\GO     721i8A
                                                         Table II.      Detonating           Cord Data--Continued

           Nomenclature       dia.(ln.)                                                                                            Packing
                                                 Coverlnlf                  Loadinlf
                                                                                                           Description                   Dimension       (inches)                      -
                                                                                                                                 Leng-th         Width          Height      (lb •• )
                                                                                                  4. 500 ft/ spool, 8
                                                                                                     spool (4,000              -------- ------ ------- -------
                                                                                                     ft)/wdn   bx
                                                                                                  5. 50 ft/spool,   100         24               17             12           94
                                                                                                     spool (5,000
   CORD, DETO-                                                                                       ft)/wdn   bx
                               0.216       Double cotton             50 grn
    NATING:                                  with wax                                             100 ft/spool, 50              21
                                                                       PETN/ft.                                                                  14*            18%        111
    fuse, prima-                             gum com-                                               spool (5,000 ft) /
    cord (PETN)                              position                                               wdn bx.
    Type II.                                finish.
  CORD, DETO-                 0.210        Cotton with              50 grn                        Packed       as required                 _
    NATING:                                  wax gum
   fuse, prima-                                                       PETN/ft.
    cord (PETN)                              finish.
    (50-ft spool
    (spliced» .
  CORD, DETO-                 0.210        Cotton with
   . NATING:                                                        Inert    -----               Packed as required.                                   ...                        _
                                             wax gum
     fuse, prima-                            composition
     cord (PETN)
  CORD, DETO-                0.235         Textile with             60 grn
    NATING: re-                              plastic coat-                                       1. 1,000 It/spool,   1         33%              11%
                                                                      PETN/ft.                                                                                 11%          77
   inforced,                                 ing.                                                   spool/crdbd   bx,
   pliofilm-                                                                                        3 bx/wtrprf
   wrapped,                                                                                         lead foil env 1
   waterproof,                                                                                      env (3,000 ft) /
   Type IV".                                                                                        wdn bx
   NATING:    re-            ------ -------------- ._-------------                               2. 500 ft/spool,  1
   inforced,                                                                                        spool sealed can,
                                                                                                                              -------- ------
   pliofilm-                                                                                        8 can (4,000
  wrapped,                                                                                          ft)/wdn   bx
  Type IV".
 CORD, DETO-                 0.235        Textile with
   NATING:  re-                                                 Inert       -----                Packed    as required
  inforced,                                 coating.
CORD, DETO-                  0.235        Textile with          60 grn
  NATING:                                                                                    200 length (1,600                 26lh
                                            plastic               PETN/ft.                                                                     18             11          57
  waterproof,                                                                                  ft)/wdn  bx
 plastic outer
 covering (8-
 ft length)
 Type I".
    • Type dnhcnatlon   In accordance         with PA-Po-417.   7 May 1954•
  •• Type t14!lhcnation In accordance         with MIlr-C-1712CA. II June 1959.

A hhreviatiou:
bx •••••        box(n)         dia •••••      diameter
                                                               ft •••••       foot     (fl!et)      lb •••••       pound<l)
              • t"ard"oard     env....        envelope
                                                              ern    ••••     ICraln (I)            nom ••••       nominal
                                                                                                                                wdn ••••
                                                                                                                                wtrprf     •••

                                                                                                                                                                     AGO 7268A
     b. Precautions in Use. The ends of detonat-           caps have lead wires of various lengths for
  ing cord should be sealed with a waterproof              connection in a circuit.   The most commonly
  sealing compound to keep out moisture ..when             used are 12 feet long. Most all have a short
  used to detonate      underwater   charges,  or         circuiting shunt or tab, to prevent accidental
  charges left in place several hours before fir-         firing, which must be removed before connec-
  ing. A 6-inch free end will also protect the            tion in a firing circuit.   If the cap is issued
  remainder of a line from moisture for 24 hours.         without a shunt, which is sometimes the case
  In priming, kinks or short bends, which may             with the M6, the bare ends of the lead wires
  change the direction of detonation and thus             must be twisted together to provide the shunt-
  cause misfires, should be avoided.                      ing action. Data on electric blasting caps is
                                                          shown in table III.
  31. Blasting Caps                                          b. Nonelectric Blasting Caps. Nonelectric
      Blasting caps are used for initiating high ex-     blasting caps (fig. 19) may be initiated by time
   plosives. They are designed for insertion in          blasting fuse, firing devices, and detonating
   cap wells, and are also the detonating element        cord. Because they are extremely difficult to
   in certain land mine firing devices. Special          waterproof, they should not be used with time
  military blasting caps are designed to detonate.       blasting fuse to prime charges. placed under
  the less sensitive explosives like TNT, military       water or in wet boreholes. If such be neces-
  dynamite, and tetrytol. Commercial caps may be         sary, however, they should be moistureproofed
  used to detonate more sensitive explosives like        with waterproof sealing compound. Those in
  tetryl and commercial dynamite, in an emerg-           use include the commercial No.6 and No.8
  ency. Two commercial caps are required to              and the special or military types I (J-1 (PETN
  detonate military explosives; however, there is       or RDX) and 1.17 (fig. 19). Special caps will
  also a priming problem as two caps will not           detonate military explosives, and the commer-
  fit into the standard threaded recess.       Both     cial caps the more sensitive types. The latter,
 military and commercial blasting caps, being           however, will detonate military explosives if
 extremely      sensitive,    may explode     unless    used in pairs; but this presents a priming prob-
 handled carefully.        They must be protected       lem, as two caps will not fit into the standard
 from shock and extreme heat and not tampered           threaded cap well. The M7 -
     special caps are
 with. Blasting caps must never be stored with          flared at the open end for easy insertion of
 other explosives, nor should they be carried in        the time fuse. Data on nonelectric caps is
 the same truck except in an emergency (para            shown in table IV.
 141 b (3) ). Two types, electric and nonelectric,
 are used in military operations.                       32. Priming Adapter M1A4
                                                            This is a plastic hexagonal-shaped      device
      a. Electric Blasting Caps. These are used          threaded to fit threaded cap wells and the MI0
   when a source of electricity, such as a blasting
                                                        universal destructor.     A shoulder inside the
   machine or a battery, is available.    Two types
                                                        threaded end is large enough to accept blast-
   are in use, military and commercial (fig. 18).
                                                        ing fuse and detonating cord but too small to
   Military caps are instantaneous, and the com-
                                                        permit passage of a blasting cap. The adapter
   mercial, instantaneous and delay. Instantaneous
                                                        is slotted longitudinally to permit easy and
   caps include the M6, the special or military, and.
                                                        quick insertion of the electric blasting cap lead
  the commercial No.6 and No. 8. No.8 commer-
                                                        wires (fig. 20). The MIA4 replaces the MIA2
  cial delay caps (fig. 18) are issued from the
                                                        and MIA3 models, which have cylindrical
  first to the fourth delay ranging from 1 :00
                                                        bodies. The hexagonal MIA4 is more readily
  second to 1 :53 seconds. \Vhen two or more of
                                                        handled by men wearing arctic mittens .
. the special instantaneous caps are used, they
  should be of the same manufacture except for          33. Adhesive Paste, M1
  the M6 caps, which regardless of manufacturer,           This is a sticky, putty-like substances for
  may be used interchangeably       as they are all     attaching charges to vertical or overhead flat
  made to a single specification. All issue electric    surfaces.  It is useful in holding charges while
AGO    726SA
                                         ......     ••   PT   WI ....

                                         ':.~...;:f;'IIC~llAS'I .. c.,

                                                   (lICTlIC      IUST'"      U,

                                                                              ..,.CI.".,.II .... C ••                                  SHORT - CIRCUITING
                                                                              DAN      •••     aue
                                                           AT LAS                 ._ ..... ,.".                                            TAB MUST BE
                                                                                                                                       REMOVED BEFORE
                                                  SPECIAL               (MILITARY)                                                     CONN ECTI NG CAPS
                                                                                                                                        IN FIRING CIRCUIT

                                                                                                        DELAY       (COMMERCIAL)

                                    M6   SPECIAL
                                    (ON CARDBOARD

             .... ----------2.350                                       IN   MAX

                                                                                             PLUG ASSEMBLY
                                                                                     SULFUR                       RUBBER

  ALUMINUM                                                                                               IGNITION     CHARGE       \
 ALLOY CUP                                                                                               ( LEAD   STYPHNATE            LEAD   WIRES
                                                                                                              AND BARIUM

                                               M6  SPECIAL
                                         (ON CARDBOARD     SPOOL)                                                 PLUG ASSEMBLY
                                                                                                                    ( RUBBER)

                                                  Figure      18. Electric             blasting           caps.

                                                                                                                                                      AGO 72Ci8A
                                                 Table     Ill.       Electric      Blasting    Cap Characteristics
                 Nomt'nclature                   Lead    wire     characteristics
                                                                                                                                  l>imenllions     (inchl'B)          Wl'hcht
                                                                                                  lX"IK"ription                                                       (Ibs.)
                                                                                                                         I.... ~th
                                                                                                                             n            Width          IIpl~ht
    CAP, BLASTING:                  com-       Short lead, 4 ft                                                            18                              12
                                                                                        500/wdn       bx    --------                       13%                         48.6
      mercial, electric,            No 6,        through 10ft
    _ instantaneous
    CAP, BLASTING:                 com-        Medium lead, 12 ft                       As required         -------- ------- -------- ------ --------
      mercial, electric,           No 6,        through 40 ft
    _ instantaneous
      mercial, electric,
                                   com-        Long lead, 50 ft                        As required          -------- ------- -------- ._----- --------
                                   No 6,         through 100 ft
    CAP, BLASTING:                  com-       Short lead, 4 ft                        1. 70/ctn. 5 ctn (350              15               12 'At              6th     22.2
      mercial                                    through 10 ft                           cap) /wdn bx
    CAP, BLASTING:                  com-       Medium lead, 12 ft                      As required          -------- ------- -------- ------ --------
      mercial electric,            No 8,        through 40 ft
    CAP, BLASTING:                                                                     As required
                                   com-        Long lead, 50 ft                                             -------- ------- -------- ------ --------
      mercial electric,           No 8,          through 100 ft
    _ instantaneous
    _ No 8, strength
                                   electric    Lead 6 ft long, copper
                                                                                                   ------------- ------- -------- ------ --------
    CAP, BLASTING:                electric,    Lead 6 ft long _______                  70/ctn                            13%                7t.4
    _ No 8, strength
                                                                                                   -------------                                               4%      8

      No 8, strength
                                  electric,    Lead 30 ft long, cop-
                                                 per tinned
                                                                                       25/ctn      ------------- ------- -------- ------ --------
    CAP, BLASTING:                electric,   Lead 12 ft long ______                                                                      13 'At
      No 8, 1st delay             (approx
                                                                                       500/wdn       bx     --------     19'h                                91.4     30

      1.00 see)
 CAP, BLASTING:                   electric,   Lead 12 ft long ______                  500/wdn        bx    --------      19th             13th             9%         30
   No 8, 2nd delay               (approx.
   1.18 see)
CAP, BLASTING:                    electric,   Lead 12 ft long ______ . 500/wdn                       bx                  19t/~            13th             9t,4
  No 8, 3rd delay
                                                                                                           --------                                                  30.5
  1.35 see)
CAP, BLASTING:       elec-                    Lead 12 ft long ______ . 500/wdn                      bx                                   13 'At                      30.0
  tric ,No.8, 4th delay
                                                                                                           ---------     19%                               9%
  (approx. 1.53 see)
CAP, BLASTING:        elec-                   Lead 6 ft long, copper                  1. 50/ctn      ----------_.         9                4%              3          2.3
  tric, high strength                           tinned                                2. 70/ctn                          14 'At             t                         8.0
                                                                                                    -----------                            7"
CAP, BLASTING:        elee-                   Lead 9 ft long, copper                  50/ctn
                                                                                                  --------------          7t,4             4%             3%          4.0
  tric, high strength                           tinned
CAP, BLASTING:                    elec-       Lead 6 ft long, copper                  50/ctn      --------------          6 'At           6               2%          2.0
  trie, low strength                            tinned
-                                                                                     As required         __________
CAP, BLASTING:                   elec-        Various    long lead                                                     -----_. ------- ------ .. _------
  tri~, inert                                   wires
CAP, BLASTING:                                Lead 12 ft long ______ . 1. lIchipbd   pkg. 50                            28t,4            15%            11%          76.5
  Sp('cial, electric                                                      pkg/fbrbd    bx, 10
                                                                          bx (500 cap) /wdn                             17t~            12'h            11           61.0
                                                                 ~        bx
                                                                       2. As r{'{Juired _______
                                                                                                                       ------- ------- -----_. --------
AGO     72:iSA
                                  Table     I II.      Electric     Blasting     Cap Characteristics-Continued

                  Noml'nclnture                                                                               Packin~                                                 -
                                             I.eall wire characteristics
                                                                                        Descrhltion                     Dimensions      Cinches)            Weight
                                                                                                                                                            (lbs. )
 CAP, BLASTING:                         Lead 12 ft long, cop-
                                                                                                                   Length       Width         Heil{ht
  special, electric, M6                                                         1/ crdbd spool, 6
                                          per tinned
                                                                                   spool/ctn, 1 ctn/             ------- ------- ------- ------ -
                                                                                   water-prf bg, 25
                                                                                   bg/fbrbd bx, 6
                                                                                  fbrbd bx (900 cap)
      A bbreviatiofU:
 1'1{ •••••
 bx    •••
              " • box CI)
                                   chipb"   •••     chipboard
                                                                           ctn •••••    carton C.)
                                   cr,lbd ••••      cardboard                                                   ft ••••••     footCfeet)
                                                                           fbrbd ••••   fiberboard
                                                                                                                1b •••••.    poundCs)

                                               ALUMINUM                                    INTERMEDIATE    CHARGE
                                            ALLOY   FERRULE                                     ( LEAD AZIDE)
                    ALLOY CUP

 0.260 IN
                                 1GNITION CHARGE
                                (LEAD    STYPHNATE
                                                                                       ,., •••
                                                                                         BASE CHARGE
                                                                                                                                                   0.241 IN

                              AND BARIUM CHROMATE)                                          (RDX)

                                                                  2.350     IN MAX

                                                       a                                       0
                                                     SPECIAL M7                   MILLITARY

                            BASE CHARGE
                                                                                                      COPPER         OR ALUM.INUM

                                  PRIMING              CHARGE
                                                                                 FLASH           CHARGE

                                                       a                                        )
                                              SPECIAL TYPE I MILLITARY
                                            Figure      19. M ilitarv nonelectric         blasting    caps.
                                                                                                                                                   AGO 7Z68A
                                                Table    IV.      Nonelectric         Blasting      Cap Characteristics
  -                                                                                                              Packing
                                                                                                                             Dimenllloni         (lnchel)            Wel~ht
                                                                               Description                                                                            (Ibl.)
                                                                                                                       Len~th           Width               Hel~ht

 CAP, RLASTING:                                                                                                         20%                  9~                8%      29
                                nonelectric,      No         1. 5,00O/wdn bx            -----------------
   6, instantaneous.                                         2. 100/ctn, 10ctn/fbrbd bx, 1 bx/                     --------_. -------- -------- ---------
                                                                wtrprf bag, 5 bag (5,000 cap) /
                                                                wdn bx
 CAP, BLASTING:                 nonelectric,      No     1. 100/ctn, 50 ctn (5,000 cap) /wdn                            18 lA,              13                 7%      50
   8, instantaneous.                                        bx
                                                         2. As required ___________________
                                                                                                                  --------- -------- -------- ---------
 CAP, BLASTING:                   special, non-          1. 50/mtl can, 20 can/fbrbd   ctn, 5                           24%                 171,4            141.4     82
   electric (Type             I(J-l»     (PETN              ctn (5,000 cap)/wdn    bx
  or RDX).                                               2. 100/ctn, 10 ctn/crdbd  bx, 10 bx                            22%                 17%              14        66
                                                            (10,000 cap) linner wtrprf pkg,                       --------- -------- -------- ---------
                                                            1 inner pkg in sawdust/outer
                                                            wtrprf pkg/wdn bx
                                                         3. As required              -------------------           -------- -------- -------- --------
  electric, M7.
                                  special,      non-     6/pprbd ctn, 1 ctn/wtrprf    bag, 50
                                                            bag/fbrbd bx, 12 bx (3,600 cap) I
                                                                                                                  --------- -------- -------- ---------
                                                            wdn bx
 CAP, BLASTING:                  tetryl,     non-        100/ctn,           50 ctn      (5,000    cap) fwdn             19                  16                8       65
   electric, type A.                                       bx
                                 nonelectric,            As required           ---------------------               --------- ------- -------- ---------
 hx •••••        hox (t'\I)     ctn •••••      carton           Ib ••••••       pound            pkJ{ ••••    J)acka~e(l)        wlln ••••        wooden
 crlll,,1 ••••   cardhoard      rhrhd ••••      fiberboard      mtl •••••       metal            pprbd ••••    paperboard        wtrprf..           waterproof

tying them in place or, under some conditions,                                                fuse or the detonation of the detonating cord.
for holding without tying. It will not adhere                                                 The 1\f2crimper forms a water resistant groove
satisfactorily to dirty, dusty, wet or oily sur-                                              completely around the blasting cap: however,
faces; becomes stiff and hard and loses its ad-                                              sealing compound should be applied to the
hesiveness at subzero temperatures;  is softened                                             crimped end of the blasting cap for use under
by water; and becomes useless if wet.                                                        water. The rear portion of the jaws is shaped
                                                                                             and sharpened for cutting fuse and detonating
34. Waterproof     Sealing Compound                                                          cord. One leg of the handle is pointed for use
   This is used to waterproof the connection                                                 in punching fuse wells in explosive materials
between the time blasting fuse and a nonelec-                                                for the easy insertion of blasting caps. The
tric blasting cap and to moistureproof primed                                                other leg has a screwdriver end. Cap crimpers
dynamite.     It does not make a permanent                                                   being made of a soft nonsparking metal (but
waterproof seal and must not be submerged in                                                 they will conduct electricity), must not be used
water unless the charge is to be fired immedi-                                               as pliers for any purpose, as this damages the
ately.                                                                                       crimping surface. Also the cutting jaws must
                                                                                             be kept clean and be' used only for cutting fuse
35. Cap Crimper
                                                                                             and detonating cord.
   The M2 cap crimper (fig. 21) is used to
squeeze the shell of a nonelectric blasting cap                                         - 36. Galvanometer
around time fuse, a standard base, or detonat-                                               The galvanometer is an instrument used in
ing cord securely enough to keep it from being                                            testing the electric firing system to check the
pulled off but not tightly enough to interfere                                            continuity of the circuit (the blasting cap, fir-
with the burning of the powder train in the                                               ing wire, wire connections, and splices) in

AGO 72li8A
                                          PR"IMING            ADAPTER
                                                                                              . .I
                                                                                         LEAD WIRES
          BLASTING CAP
                                                      MIA 4


                            NON ELECTRIC
                           BLASTING   CAP

                                                                               TIME    FUSE

                                                        MIA 3

                                     Figure   fOe   Priming   adapters.

order to reduce the possibility of misfires (fig.
22). Its components include an electromagnet,            of the needle deflection depends on the amount
a small special silver-chloride dry cell battery,        of resistance in the closed circuit and on the
a scale, and an indicator needle. 'Vhen the two          strength of the battery.      The galvanometer
external terminals are connected in a closed             must be handled carefully and kept dry. It
circuit, the flow of current from the dry cell           should be tested before using by holding a piece
moves the ,needle across the scale. The extent           of metal across its two terminals.   If this does
                                                         not cause a wide deflection of the needle (23 to
                                                                                                 AGO 72/iRA
                            CUTTING     JAWS

             Figure   fl.   M2 Cap crimper.

  25 units) the battery is weak and should be re-
  placed. Being delicate, the instrument must
  not be opened except to replace a weak cell.
  When used in a cold climate, the galvanometer
  ~hould be protected from freezing by keeping
  It under the clothing near the body, as dry cell
  batteries tend to cease functioning at tempera-
 tures below O°F.      .
     CAUTION: Only the special silver-chloride
                                                                   Figure   2f.   Galvanometer.
 dry cell battery BA 245/U, which produces only
 0.9 volts, is to be used in the galvanometer, as
 other batteries may produce sufficient voltage                    and grasp the bottom of the machine.
 to detonate electric blasting caps. Because of              (5) Grasp the handle with the right hand
 the tendency to corrode, the battery should be                    and turn it vigorously clockwise as far
 removed (rom the gal\'inometer when it is not                    as possible.
 to be used (or extended periods.                        b. Thirty-Cap Blasting J.fachine. This de-
                                                     vice fires 30 electric caps connected in series.
37. Blasting Machine
                                                     It weighs about 20 pounds. To operate:
   a. Ten-Cap Blasting ltfachine. This is a                 (1) Raise the handle to the top of the
small electric impulse-type generator that pro-                   stroke.
duces adequate current (45 volts) to initiate               (2) Push the handle down quickly as far
10 electric caps connected in series if the handle                as it will go.
is rotated to the end of its travel.     It weighs      c. Fifty-Cap and One-Hundred Cap Blasting
approximately 5 pounds (fig. 23). The opera-         J.fachines.
tion is as follows:                                         (1) The 50-cap machine fires 50 electric
      (1) Try the machine to see whether or                      caps connected in series (fig. 23). It
           or not it works properly.    Operate it               weighs about 20 pounds.       Operation
           several times until it works smooth-                  is as follows:
           ly before attaching the firing wires.              (a) Raise the handle to the top of its
     (2) Fasten the firing wires tightly to the                     stroak.
           terminals.                                         (b) Push the handle down quickly as
     (3) Insert the handle.                                         far as it will go.
     (4) Insert the left hand through the strap            (2) The 100-cap machine is similar to the
AGO 72liSA
                                              CARRYING          STRAP

                                              HAND GRIP

                                                                    FIFTY- CAP BLASTING

            TEN -CAP BLASTING

                                     Figure    23.   Blasting   machines.

         50-cap machine except for size and
         weight and is operated in the same              is the two-conductor, No. 18 AWG plastic-
         manner. Both are adequate for firing            covered or rubber-covered type. It is carried
         their rated capacity of electric blast-         on the reel unit RL39A, described below.
         ing caps connected in series.                   Single-conductor No. 20 AWG annunciator wire
                                                         in 200-foot coils is issued for making connec-
38. Firing Wire and     Reel
                                                         tions between blasting caps and firing wire.
   a. Types 01 Firing lVire. 'Vire for firing
electric charges is issued in 500-foot coils. It         'VD-l/TT    communication wire may also be
                                                         used. However, it has a resistance of about
                                                                                               AGO 72MIA
40 ohms per 1000 feet, which increases                  the             handles are made of two' U-shaped
POwer requirement (table XXI, app E).                                   steel rods .. A loop at each end en-
      b. Reels.                                                         circles a bearing assembly, which is
         (1) RL39A.       This consists of a spool that                 a brass housing with a steel center
                accommodates 500 feet of wire, a                        to accommodate the axle. The crank
                handle assembly, a crank, an axle, and                  is riveted to one end of the axle and
                two carrying straps (fig. 24). The                      a cotter pin is placed in the hole at
                fixed end of the wire is extended from                  the other to hold the axle in place.
                the spool through a hole in the side                (2) 500-loot reel with detachable handles.
                of the drum and fastened to two brass                   This is a metal drum mounted on an
                thumbnut terminals.      The carrying                   axle to which two detachable D-
                                                                        shaped handles are fastened.       The
                                                                        arm with the knob on the side of the
                                                                        drum is used for cranking (fig. 25).


                                                                    Figure   t5.   Reel with detachable   handles.

                                                                   (3) lOOO-loot reel. This is similar to (2)
                                                                       above, except that it has a capacity of
                                                                       1000 feet of firing wire.

                                                               39. Detonating     Cord Clip
                                                                 The r.ll detonating cord clip (fig. 26) is used
                                                              to hold together two strands of detonating cord
                                                              either parallel or at right angles to each other.
                                                              Connections are made more quickly with these
                                                              clips than with knots. Also, knots may loosen
                                                              and fail to function properly if left in place any
                                                              length of time. Joints made with clips are not
                                                              affected by long exposure.
                                                                 a. Branch Line Connections.       Branch lines
                                                              of detonating cord are connected by clipping
                                                              the branch line with the U-shaped trough of
                                                              the clip, and the main line with the tongue
                                                              of the clip, as shown in figure 26.
                                                                 b. Connecting Two End.~. Ends of detonat-
                  Figure    ,U.   Firing   wire reel.         ing cord are spliced by overlapping them about

AGO   7268A                                                                                                          33

      323-&61 0 • 1I8 • 3
                                                            by means of blasting caps or mine activators.
                                                           with standard firing devices. The destructor
                                                           has booster cups containing tetryl pellets. The:
                                                           chief function of the destructor is the conver-
                                                           sion of loaded projectiles and bombs to im-
                                                           provised demolition charges and the destruc-
                                                           tion of abandoned ammunition (fig. 27).j


                   CLIP      BEFORE      BENDING

                                                             CLOSING      PLUG                      AMMUNITION      BUSHING

                                                           WITH   CO~E~              ~/~                                      1

               SPLICING       TWO CORDS                     BLASTING  CAP                      BOOSTER       ASSEMBLY

                                                                          Figure   27.     M10 destructor.

                                                              b. },[19 Explosive Destructor.       This device
                                                           (fig. 28) consists of an explosive-filled cylindri-
                                                          cal body with a removable pointed ogive~ which
                                                          may be discarded if not needed. This destruc-
                                                          tor may be primed with a delay detonator, de-
                                                          lay firing device with a special blasting cap, a
                                                          nonelectric special blasting cap initiated by
                                                          time blasting fuse or detonating cord, or an
                                                          electric special blasting cap. The cap well on
              BRANCH         LINE   CON NECTION           each end is threaded to receive the standard
                                                          base coupling or a priming adapter.         This de-
              Figure   26.   MJ Detonating   cord clip.   vice is particularly suitable for use with the
                                                          dust initiator, described in paragraph 8, appen-
                                                          dix E, and similar charges.       .
 12 inches, using two clips, one at each end of
                                                             c. J',Jl Concussion Detonator.   The Ml con-
the overlap, and bending the tongues of the
                                                          cussion detonator is a mechancal firing device
clips firmly over both strands.  The connection
                                                          actuated. by the concussion wave of a nearby
is made secure by bending the trough end of
                                                          blast (fig. 29). It fires several charges simul.
the clip back over the tongue (fig. 26).
                                                          taneously without connecting them with wire
40. Firing Devices and Other Accessory                    or detonating cord. A single charge fired in
    Equipment                                             any way in water or air will detonate all
     a.    Universal l/igh Explosive Destruc-
          J',[10                                          charges primed with concussion detonators
tor.  The MI0 destructor is a high explosive              within range of the main charge or of each
charge in , assembled metal device initiated
           an                                             other (table V). Detonators frequently func-
                                                          tion at ranges greater than those in table V,
                                                                                                                 AGO 72G8A
                                                                                                                                SHIPPING PLUG
                                 SHIPPING PLUG

                                                                                             COMPOSITION                 THREADED CAP
                                                                                              PELLETS                         WELL

                                                                                                                                      ,2.0 IN

           I.                                                   Figure       f8.
                                                                                   16.4 IN   ----......1'
                                                                                     M19 explosive   destructor.

but their reliability is then not assured. They                                                  d. Jt!IAI I5-Second Delay Friction"Detona-
should not be used in surf at depths greater                                                  tor.
than 15 feet, as they function by hydrostatic                                                       ( 1) C harac teris tics ( fig. 30) . This de-
pressure at a depth of 25 feet. Further, if the                                                              vice consists of a pull friction fuse
salt delay pellet is crumbled due to long stor-                                                              igniter, 15-second length of fuse, and
age, the detonator should not be used on under-                                                              blasting cap. The blasting cap is pro-
water charges.                                                                                               tected by a cap screwed on the base.

 Table     V.        Operating     Range         0/    Concussion        Detonators                  (2) Installing.
                                                                                                       (a) Unscrew cap protector from base.
                                   In    water                         In air                          (b) Secure device in charge.
                          D..pth of
                                          ranlCfI Ut)
                                                                    ranlffl Ut)
                                                                                                e. Jt[IA2 (Jt[IEI) I5-Second Delay Percus-
                             Ut)                                                             sion Detonator.
                                                      P    =    99%      P    =     99'10          (1) Characteristics (fig. 31). This item
       0.5                   2                   . 10          -                   -                      consists of a firing pin assembly joined
       0.5                   4                     60          -                   -                      to a delay housing and primer holding
       0.5                   6                     80 .        -                   -                      assembly.
       0.5                   8                     80          -                   -                 (2) Installing.
       2.5                  -                     -            12.5             10.8
       2.5                   2                    20           -                   -                   (a)     Remove cap protector.
       2.5                   4                    80           -                   -                   (b)     Screw device into threaded cap well.
       2.5                   6                    90           -                   -           f. Jt!2AI (Jt!2EI) 8-Second Delay Percussion
       2.5                   8                   150           -                   -         Detonator.
       5                    -                     -            14.1            11.5
                                                                                                  (1) Characteristics (fig. 32). Except for
      10                    -                     -            18.8            15.7
                                                                                                          the delay period, marking, and shape
      15                    -                     -            21.5            18.0
                                                                                                          of the pull ring, the 8-second delay
                            ---                  -             25.2            21.2
      20                     2                    2J           -                   -                      percussion detonator is identical with
      20                     4                    80           -                   -                      e, above, in construction, functioning,
                                                                                   -                      and installing.
                                                                                                     (2) Installing.
    P=Prohahlllty       that detonator     at    IndlcaW   dl.tance      ,,-Ill be rune-               (a)    Remove cap protector.
t Iunecl hy Inltiatinll    charlll!.

AGO 7258A                                                                                                                                       35

                          SALT BARREL PLUG
                                                 ~w    I
                                                                           SNAP DIAPHRAGM
                         SALT DELAY TABLET
                                   SAFETY PIN     hI
                                       SPACER~.                                PROTECTIVE

                                                                           CATCH SPRING
                          FIRING PIN
                               SAFETY BALL
                                  POSITIONING SPRING                       RUBBER

                                                                                              END VIEW WITH DIAPHRAGM COVER
                                                                                              AND DIAPHRAGM REMOVED TO SHOW
                                                                                              CATCH SPRING ASSEMBLY

                                                  Figure 29.   Ml Concussion    detonator.

          (b)   Screw device into threaded cap
                well.                                                                  tected by a cap screwed on the base.
                                                                               (2) .Installing.
     g. },[2 8-Second Delay Friction Detonator.
        (1) Characteristics (fig. 33). This device                                (a)    Unscrew cap protector from base.
             consists of a friction-type fuse light.                              (b)    Secure device in charge.
             er, an 8-second length of fuse, and a                        h.       Delay Firing Device.
             blasting cap. The blasting cap is pro-                            (1) Characteristics (fig. 34).

36                                                                                                                  AGO 72ljSA
                 I~'    ----GIN

                                 CAP     PROTECTOR
         DE TONATOR     CHARGE


                                Figure    30.    MIAI     IS-second    delay friction    detonator.

                                                                                   NOTE: CIRCULAR RING
                                                                                   INDICATES FIFTEEN-
                                                                                   SECOND DELAY

                                                1- REMOVE     CAP PROTECTOR
                                            2 SCREW INTO EXPlOSIVE
                                            3- REMOVE SMALL COTTER PI N
                                            4- PULL PULL RING TO FIR

                                                     PERCUSSION        PRIMER


                                                          HOLE (3)

                      Figure   31.   MIA!       (MIEl)     IS-8econd    delay     percu8sion   detonator.

AGO   7258A                                                                                                               37
     NOTE: T-HANDLE                PULL
     RING IDENTIFIES               8-

                                                                                        CAP PROTECTOR

                                                                                   7.39 IN MAX-                                        _



                                                                                                                                      BLASTING          CAP
                                                                           FIRING        PIN
                                                                                                           DELAY                CHARGE

      3. REMOVE     SMALL       COTTER         PIN
      4. PULL    PULL    RING      TO    FIRE

                             Figure      82.    M2Al        (M2El)       8-second     delay percussion          detonator.

         Cas~                   Color                       Dimensions
                                                        D                 L                 Internal   action
Copper   and    brass    Natural        metal        7116    in      6%       in      Mechanical  with             cor-
                                                                                                                                1 min to 23 days, iden- ~
                                                                                       rosive chemical            re-
                                                                                                                                  tified by color of safety
                                                                                                                                  strip ..

Colored metal strip     inserted    in slot above percussion
   cap.                                                                       10 units--2 red, 3 white, 3 green, 1 yellow, and 1 blue-
                                                                                and a time delay table packed in paperboard carton,
                                                                                10 cartons in fiberboard box, and 5 boxes in wooden

     (2) Installing.
        (a) Select device 0/ proper delay (table                                                   to make sure that firing pin has not
            VI).                                                                                   been released. If the firing pin has
        (b) I nsert nail in inspection hole to                                                     been released, the nail cannot be
                                                                                                   pushed through the device.
                                                                                                                                                   AGO 7ZliRA
                                      , ,.
                                      C'l      00

                                                                               ~        00

                              ti                 CIS
                                                          "'C      ... ... ... c::
                                                              ... .s:: .s:: .s:: Os

                                                          N ..,.
                                                          C'l                          (I";)        .-4

                                                                       N roiLQ                                (l)
                    :l                         .-4                                                            (I";)


                             ::it                           CIS      CIS
                                                                                     ... ...
                                                                                ... .s:: .s:: c::
                             0                  CIS
                                                          "'C      "'C                        Os
                                                          0        C':l     LQ
                                                                                       C\!          10
                                               C':l       ~        roi      roi        10           N         0
                                               C'l                          .-4                               00

                                                 CIS                     ...
                                                                    ... .s::             c::          c::         c::
                                                                   .s::                Os           Os        Os
                                               00                  0        LQ

                ~                              M          0        ~        N          LQ
                                                                                                    (I";)     .-4
               .2                                         C'l
                             ::it              CIS                   ... ...
                                                           ... ... .s:: .s:: .5 c::
                                                                              S Os
                                                                   ..,. ~10 LQ
                                                                                       N        0             (l)
                                                                   .-4                          00            ~           u
                                                           ... .s::            e::      c::          c::        c::
                             en               "'C
                                                         .s::              .s         Os        Os            Os
                                                         00        N       0

                             ...                CIS
                                              "'C               ... ...
                                                           ... .s:: .s:: .sc:: .sc:: Os
                                              (l)                          LQ
                                              N          to-
                                                                   (l)     N          0

                                       CIS          ...
                                               ... .s::             c::     c::         c::         c::        d        °t
                            en       "'C
                                              .s::                Os       Os Os .s Os                                  't:
                                                                           ~ ..,. en
                                     C':l                10
                                     roi      00         N        LQ                                         (l)
              ~                                                   10       C'l        .-4                                 C
              :c                                                                                                        'iij

              ~                                                                                                          ..
                                               ... ...
                                              .s:: .s:: ... ... c:: c:: c::                                             c
                                                        .s:: .s:: .s Os Os
                            ::it                                                                                         o
                                              10   10
                                     C':l     ~
                                                         ~        C'l      .-4        C'l       0            10
                                                                                                C'l          .-4         Ii

                                                                                       c::                    e::

                                      ...      c::        c::      c::      c::      Os             c::      .s

                            ti      .s::

             ~                                                                                                          '5
                                              c::         c::c:: c:: c:: c::
                                                  Os :s c:: Os Os Os Os                                                 1
                           ~                 Os                                                                          :l
                           0        10
                                    oci      ..,. C'l to- 10 00 10 ~
                                             LQ         LQ
                                                                  .-4      .-4

                                                                                      c::       c::
                                             .s::        c::       c::     c::       Os        Os            c::
                                                        Os        Os       Os                               Os          o
                                                                           ..,. N    0         10                       !
                                             N          cc
                                                                  to-                          roi          .-4         ...
                                                         c::      c::      c::        c::       c::          c::
                           ::it               ...
                                                        Os        Os       Os        Os        .s           Os
                                             00         (l)
                                                                  ~.en               10
                                                                                               ..,.         C':l

             c.~                    LQ                  LQ        0        10        0         LQ           0
             EIIl                   C'l
                                                        C'l       10       ~         0         C'l          LQ

             ~~                      I
                                                        +                            .-4       .-4          .-4

AGO 721iSA
                       CAP PROTECTOR                                                               (c)
                                                                                                         Remove protective cap from base.
                                                                                                   (d) With      crimper   attach nonelectric.
                                                                                                         blasting cap to base. Crimper jaws.
                                                                                                         should be placed no further than.
        ------                     5-3/8    IN                                                           ~ inch from open end of blasting I.
                                                 T PULL- RING IDENTIFIES                           (e)  Secure firing device in charge.
                                                    8 - SECOND DELAY
                                                                                                   (f) Crush     glass   ampoule     between
     DETONATOR                                                                                         thumb and fingers.
     CHARGE                                                                                        (g) Remove safety strip.

                                                                                                          Caution: If safety strip does not
             STANDARD                                                                                  remove easily, remove and discard

       Figure         33.   M2 8-second delay friction        detonator.                   i. M1A1 Pressure Firing Device.
                                                                                              (1) Characteristics (fig. 35).
             CRIlt'                                                  Dimensions
                                                              D                       L                  Internal   action
                                                                                                                               Operating    pressure
     Metal                           OD              % in
                                                                                  2   *   in         Spring-driven           20 lb or more.
                                                                                                        striker with
                                                                                                       trigger pin
                                                                                                       and keyhole
                                                                                                       slot release.

                                      [                                      6 1/4 IN ~

                                      ~)J.                                                     ]
              IDENTIFICATION                AND
              SAFETY     STRIP              (COLORED
              ACCORDING     TO               DELAY)


                                                                                                PIN                 GLASS  AMPOULE::
                                            COUPLING  BASE
                                            (NOT TO BE                                                              (CRUSH BETWEEN
                                            REMOVED)                                                                THUMB AND FOREFINGER)
         (ALWAYS REMOVE)

                                                     Figure       3-'.   Ml delay firing       device.
                                                                                                                                           AGO   72TiRA
                                 SAFETY PIN---......
                                 (POSITIVE)-      "
                                 REMOVE LAST



                                                                                                        KEYHOLE    SLOT
                                                                                                        RELEASE   PIN

                                   Figure   35.   MIA!     pressure   firing   device.

_             SafeUes             Ac~rles                                                Pat'kalflnlf

Safety fork and positive   3-pronged pressure            Five units, with percussion caps packt>d in cardboard          carton.
  safety pin.                 head and extension           Fifty cartons shipped in woodt>n box.

AGO   7268A
     (2) Installing.
                                                                             and extension rod and screw in top
       (a) Remove      protective cap from base                              of pressure cap, if needed.
              and crimp on a nonelectric blasting                       (c) Attach     firing device assembly to
              cap.    Crimper    jaws should be                              charge.
              placed no farther than 'i4 inch from                      (d) Remove safety fork first, and posi-
              open end of blasting cap.                                      tive safety last.
                                                                  j. !fl. Pull Firing Device.
       (b)    Assemble 3-pronged   pressure         head
                                                                     (1) Characteristics     (fig. 36).


                                                                                       ~lih .

                                                                                            ")    LOCKING
                            SAFETY PIN

                                                                        TIE     DOWN

                       /          POSITIVE
                                 SAFETY PIN
                              (REMOVE LAST)


                                    Figure    36.    Ml    pull firing    device.

                                                                                                              AGO 725BA
              Calle                                                                                                     Intl'rnal   action                 Opl'ratinlC      force
                                                                      D                        L

     Metal                                   OD                    9/16 in                  3 5/16 in               Mechanical           with         3 to 5 lb pull on trip
                                                                                                                     split-head           striker       wire.

                                             Safl'tit. ..                                                                            PackalCinlC

    Locking         and positive     safety         pins.                                     Five units complete with percussion caps and two 80-ft
                                                                                                spools of trip wire are packed in chipboard container.
                                                                                                Forty chipboard containers are packed in wooden box.

       2. Installing.                                                                                   (c) Attach  firing device assembly to
            (a)       Remove protective cap.                                                                charge.
            (b)       With crimpers,    attach nonelectric                                              (d) Attach anchored pull wire.
                      blasting cap to standard       base.                                              (e) Remove locki1ig safety pin first, and
                      Crimper jaws should be placed no                                                      positive safety pin last.
                    . farther than 1,4 inch frotn open end                                          k. ltf3 Pull-Release Firing Device .
                      of blasting cap.                                                                 (1) C1zaracteri.~tics (fig. 37).

                                                                                                                        Internal    action              Opl'rRtinlC      presllure
              Calle                   Color
                                                                      D            I           L

    Metal                                   OD                 9/16 in                       4 in               Mechanical   with                     Direct pull of 6 to
                                                                                                                 spreading     striker                  10 lb.
                                                                                                                 head release.

                                            Saleti ....

    Locking and positive            safety       pins.                                       Five units with two 80-ft spools of trip wire in carton,
                                                                                               and 5 cartons packed in wooden box.

         (2)          Installing.                                                                             (d)  Secure one end of trip wire to
                                                                                                                  anchor and place other end in hole
                (a)     Remove protective                     cap.
                                                                                                                  in winch.
                (b)     \Vith crimpers, attach blasting cap                                                   (e) \Vith knurled knob, draw up trip
                        to standard base.     Crimper jaws                                                        wire until locking safety pin is
                        should be placed no farther than 1,4                                                      pulled into wide portion of safety
                        inch from open end of blasting cap.                                                       pin hole.                        .
               (c)      Attach firing device to anchored                                                      (f) Remove locking safety pin first and
                        charge (must be firm enough to                                                                positive safety pin last.
                        withstand   pull .of at least 20                                            1. ltf5 Pressure-Release Firing Device.
                        pounds).                                                                        (1) Characteristics (fig. 38).
-                                                                              Dlmenlionl
            Calle                                                                                                             Internal       action        InltlRtlnll     action
                                                               L                     W                  lit

Metal                           OD                          1 % in            15/16 in              11116 in            Mechanical with                 Removal of
                                                                                                                         hinged plate                     restraining
                                                                                                                         release.                         weight-5    lb
                                                                                                                                                          or more.
                                           Safeti ....

Locking safety            pin and hole for improvised                     positive          Four firing devices complete and four plywood pressure
   safety pin.                                                                                boards in paper carton. Five cartons are packaged in
                                                                                              fiber board box and ten of these in wooden box.

AGO     7268A                                                                                                                                                                        43
     (REMOVE        LAST)~

                       PROTECTIVE CAP
                       (ALWAYS REMOVE)

                                   ANCHOR          CORD
                               FIRING        PIN                                                                      I
             PERCUSSION                                                                        PIN

                                   COUPLING           BASE

                                    Figure   37.    M3 PUll-release   firing   device.

     (2) Installing.
       (a)   Insert a length of 10-gage wire in                              or 18 gage wire. Bend wire slight.
             interceptor hole.                                               Iy to prevent dropping out.
       (b)   Bend slightly to prevent dropping                           (e) Remove protective cap from base
             out.                                                            and with crimpers, attach blasting
       (c)  Remove small cotter pin froIl)                                   cap.    Crimper    jaws should be
            safety pin.                                                      placed no farther than 1)1, inch from
       (d) Holding release plate down, replace                               open end of blasting cap.
          , locking safety pin with length of 16                         (f) Secure firing device assembly in
                                                                                                         AGO 72r.8A
                                                                   pull on the striker retaining pin causes the
                                                                   striker to hit the primer, igniting the fuse. A
                                                                   sealing compound is applied between the fuse
                                                                   and the lighter to retard any flash that may
                                                                   come from lighting the fuse.
                                                                      n. ltl60 lVeatherprool Fuse Lighter.        This
                                                                   device is designed to ignite blasting fuse in all
                                                                   sorts of weather conditions and under water if
                                                                   waterproofed.      The fuse is inserted into a fuse
                                                                   retainer and sealed and weatherproofed           by
                                                                   means of two rubber washer seals (fig. 40). A
                                                                   pull on the pull ring releases the striker as-
                                                                   sembly, allowing the firing pin to drive against
                                                                   the primer, which ignites and initiates the
                                                                   fuse. For further information, see paragraph
                                                                      o. Computing Tape. The demolition charge
                                                                   computing tape (fig. 41), provides a rapid
                                                                   method of calculating the weight of TNT (in
                                                                   pounds) needed to carryon a demolition proj-
                                           INTERCEPTOR        OR   ect. It combines in an abbreviated form most
                                                                   of the formulas and tables provided in this text.
                                                                   The assembly consists of two 6-foot flexible
                                                                   steel spring retractable tapes in joined metal
                                                                   housings.     The two tapes have a total of five
 LOCKING                                                           sets of markings.       A rigid embossed scale is
                                                                   mounted on one side of the housing. The scales
                                                                         (1) First tape (breaching and pressure
                                                                              scales). The upper side of this tape
    Figure     98.   M5 pressure-release   firing   device.                   indicates the pounds of TNT required
                                                                              to breach concrete, masonry, timber,
                                                                              or earthen walls, making allowances
         (g)  Emplace charge and set the re-                                  for the tamping and placement of
             straining   weight    (5 pounds or                               charges. The weight is read directly
             more) on top. of the firing device.                              to the right of the mark that indicates
         (h) Slowly and caref.ully, without dis-                              the thickness of the wall or obstacle.
             turbing the restraining weight, re-                              The lower side of the tape has infor-
             move the improvised locking safety                               mation on breaching concrete beams,
             pin first and the improvised posi-                               roadways, and bridge spans.        It is
             tive safety pin from the intercep-                               used to measure the thickness of the
             tor hole last. The pins should re-                              target or element. The weight of the
             move easily if the restraining                                  charge may be read directly from the
             weight is adequate and positioned                               tape without consideration of the ac-
             properly.                                                       tual dimensions of the target.
   1n. },!2 lVeatherprool Lighter.  This device                         (2) Second tape (steel- and timber-cutting
,:as designed as a positive method of lighting                               scales) . This tape contains the re-
tIme blasting fuse (fig. 39). It operates ef-                                quirements for cutting steel and tim-
fectively under all weather conditions-even                                  ber construction materials.     One side
under water if it is properly waterproofed.   A                              shows the weight of TNT needed for

AGO 72r.8A                                                                                                        4S




       PAPER    TUBE

                   Figure       39.    M2 weatherproof       fuse    lighter.

                                                                                    TIME   FUSE

                          c=====o                                                                 VENT

                                                                                 PERCUSSION       PRIMER

                                             SMALL      WASHER                                     SHIPPING

                                                             LARGE      WASHER                COLLET

                       Figure    ,",0. M60 weatherproof          fuse lighter.

46                                                                                                         AGO 7268A
                                                                        point and a coarsely knurled body to
                                                                        provide maximum holding power in
                                                                        light steel, softer metals, concrete, and
                                                                        heavy wood. The sabot, an annular
                                                                        threaded unit, screws on the rear of
                                                                        the fastener to guide it in ejection,
                                                                        acts as a stop-shoulder, and provides
                                                                        additional bearing on the penetrated
                                                                        material.     The cartridge case is a
                                                                        specially wadded caliber .38 steel case.
                                                                        A manual device is provided for cock-
                                                                        ing the driver under water.

                  Figure   41.   Computing   tape.

           cutting timber for both internal and
           external placement.   The reverse side
           has a rule for the calculation of the
           cross-sectional area of steel members
           and also the formulas for cutting
                                                              OJ            00
       (3) Bar and rod-cutting sca.le. The small
           scale on the exterior of the case is
           used for making calculations for the
                                                                                         ~~.               ]
           cutting of rods, bars, chains, and                              F1'gure 42.   Ram-set   gun.
           cables. The number of pounds of TNT
           needed for cutting is read directly                     (2) Operation. The firing of the cartridge
           from the scale.                                             propels the fastener and sabot into
   p. Demolition Card. This pocket sized card                          the target.     The fastener acts as a
(GTA 5-10-9, l\1ay 65) gives data in tabulated                         rivet for attaching charges to steel,
form for the calculation of' pressure, timber-                         concrete, or wooden targets.    The de-
cutting, steel-cutting, breaching, and cratering                       vice is especially useful where work-
charges.                                                               ing space is severely limited and for
  q. Rivet-Punching          Powder-Actuated         Driver            underwater work. Do not fire the gun
(Ram-Set       Gun).                                                   into e.rplosive or immediately adjacent
       (1) Description.   This is a riveting ma-                       to exposed explosives.
           chine powered by the gases generated                   r. Earth Augers and Diggers. Two types of
           by a fired cartridge (fig. 42). It is              earth augers, hand-operated and motorized, are
           hand-operated,   air-cooled, and feeds             used for boring holes for the placement of
           from a magazine with a 10-cartridge                cratering charges and bridge-abutment      demo-
           fastener unit capacity.     It operates            lition charges.    l\Iotorized earth augers will
           effectively under water.    The water-             bore holes to a depth of approximately 9 feet.
           proofed fastener unit has a sharp                  Boring speed depends on the type and consist-

AGO   72r;~A                                                                                                   47
ency of the soil, being most rapid in light earth
or loam. Earth augers and diggers cannot be
used satisfactorily    in soil containing     large
      (1) Hand-operated posthole auger. The
           10-inch posthole auger (fig. 43) is
           capable of boring a hole large enough
           for the 40-pound ammonium nitrate
           cratering charge and other charges of
           equal size. The extension handle per-
           mits boring as deep as 8 feet.
      (2) Posthole digger. This tool (fig. 43)
           has two' concave metal blades. on
           hinged wooden handles.      The blades
           are forced into the earth and the soil
           is removed by lifting and pulling the
           handles apart.
      (3) Motorized earth auger.

           earth augers drill hole 8, 12, 16, or 20
           inches in diameter to depths up to 8

   8. Pneumatic Tools. These are the rock drill,
pavement ~reaker, and wood-boring machine.
The rock drill bores holes up to 2 inches in                                                                                             i
diameter in rock, concrete, or masonry for the
placement of internal charges. The pavement
breaker is used to shatter the hard surface of
roads before drilling boreholes with an auger
for cratering charges.     The wood-boring ma-
chine drills boreholes in wood for the placement
of internal charges.
41. Blasting Kits                                                                                                                        t
   These kits or sets are assemblies of demoli-
tion explosive items, accessories, and tools
needed for various jobs. They are issued ac-
cording to tables of equipment.
   a. Electric and Nonelectric Kit. The electric
                                                                          A. POSTHOLE                      B. POST HOLE
and nonelectric demolition equipment set con-                                    AUGER                         DIGGER
sists of TNT and :M5A1 (Composition C-4)
demolition blocks and accessories for electric                   Figure    43.    lland-operated          digging      tools.
and nonelectric priming and firing (fig. 44).
The set is carried in the engineer squad and              Qua"tity'                                       Item
platoon demolition chest.
                                                             5            Box, cap, ten-cap       capacity,        infantry
      (1) Components issued as basic kit. The
                                                             1            Chest, demolition, engineer platoon,                  M1931
          basic kit consists of items listed below.          2        .   Crimper, cap, M2 (w/fuse     cutter)
          These may be requisitioned separately              1            Galvanometer,       blasting,       (w /leather        case
          for replacement purposes.                                         and carrying       strap)
 (J,uu.'it"                            ltftrt                2            Knife, pocket
     2          Bag, canvas, carrying,   demolition kit
                                                             2            Pliers, lineman's       (w / side      cutter),       length
     1        , Blasting machine, ten-cap capacity
                                                                             8 in

48                                                                                                                          AGO 72r.SA
                                                                      CARRYING BAG

                          CAP    BOX

                                                DEMOLITION      CHEST

                                                       ,:                            :;w~~
                                                                                       COMPUTING    TAPE

                                WIRE REEL
                                       Figure   .H. Electric   and 1Ionelectric   blasting   kit.

AGO 726SA                                                                                                  49

    323-l\61 0 • 68 • 4
 Quantity                                  Item
          1      Reel, wire,. firing, 500 ft, RL-39A," (wI                (2) Components issued separately.      The
                   carrying   straps, w Iwinding device, wI                   following items are required to com-
                   spool, w/o wire)                                           plete the kit and should be on hand at
     .2         Tape, computing,     demolition charge
                                                                              all times. They must be requisitioned
                                                                              separately, however.
          (2) Components issued separately.        The                           (a) Nonexplosive             components.
               following items are required to com-                   Quantity
               plete the kit and should be on hand at                    20          Adapter,      priming,     MlA4
               all times. These items are not sup-                        2          Adhesive, paste,         for       demolition      charges,
               plied with the kit, and must be requisi-                                % lb can M1                  .
               tioned separately.                                        50          Clip, cord, M1, detonating
                                                                          2          Insulation tape, electrical, black adhesive,
             (a) Nonexplosive components.
 (Juantity                                 Item
                                                                                       *    in wide
      60          Adapter, priming, MIA4                                             Sealing compound, blasting       cap, water-
       2          Adhesive, paste, for demolition charges,                              proof, % pt can
                     lh -lb can, M I
          1                                                                      (b) Explosive        components.
                  Cable, power, electrical, firing, vinyl poly-
                    mer insulation,      two conductor, No. 18                                                          Item
                                                                         50          Cap, blasting,      special,        nonelectric,     M7
                     A wa stranded, 500-ft coil.
      50          Clip, cord, MI, detonating                             40          Charge, demolition,            block, M5Al,         2% lb,
          6       Insulation tape, electrical, black adhesive,                         Comp C-4
                     %-in wide                                            2          Cord, detonating,         fuze, primacord,           100 ft
          1       Sealing compound, blasting          cap, water-                      spool
                     proof, lh-pt can                                      2         Destructor,     explosive,         universal,      M10
          2     Twine, hemp, No. l8,8-oz. ball                            2          Fuze, blasting, time, 50-ft coils
          2       Wire,      electrical,   annunciator,    waxed
                                                                         50          Igniter, blasting fuze, M60, weatherproof
                     double cotton wrapped insulation, solid
                     single conductor, No. 20 AWa, 200-ft
                     coil                                              c. Earth Rod Kit.

              (b) Explosive      components.                               (1) Use. This kit (fig. 46), is used for
                                                                               making holes for demolition or con-
      50          Cap, blasting, special, electric M6                          structional purposes as deep as 6 feet
      50          Cap, blasting, special, nonelectric M7                       and as large as several inches in di-
      40          Charge,     demolition,     block, M5Al 2'h-Ib               ameter in earth and soft shale. It is
                    Comp C-4                                                   not usable in rock or other' hard ma-
      50          Charge,     demolition,     block, 1-lb (TNT)
                                                                               terial.   The rod is driven into the
                  Cord, detonating,       fuze, primacord,  lOO.-ft
                     spool                                                     earth by the propelling charge, which
          5       Destructor,    explosive, universal     MIO                  is exploded in the firing chamber.      A
          2       Fuze, blasting, time, 50-ft coils                            removable handle      (extractor    rod),
      50          Igniter, blasting fuze M60, weatherproof                     which fits through the holes in the
                                                                               firing chamber, and an extension are
     b. Nonelectric Kit.                                                       used for gripping and lifting the rod
        (1) Com]Jonents issued as ba,(lic kit. The                             or pulling it from the earth. A linear
            basic kit (fig. 45) consists of the items                          charge is furnished for enlarging the
            listed below. These items may also                                 diameter of the hole. A forked in-
            be requisitioned    separately    for re-                          serting rod also is furnished for in-
            placement purposes.                                                serting    improvised   linear   charges
 Cju4nfit"                                  Item                               when the standard ones are not avail-
      2          Bag, canvas, carrying,   demolition kit                       able.
          2       Box, cap, lO-cap capacity, infantry
      2          Crimper, cap, M2 (w/fuse cutter)                          (2)     Components.
      2          Knife, pocket                                                      Note. The item letters   in                (a)      and    (b)
      2        , Tape, computing,  demolition charge                             below are keyed to figure 46.

so                                                                                                                                   AGO 72fi8A
             CARRYING     BAG
                                                                        CAP BOX

                                        COMPUTING          TAPE
                        Figure   -,s.   Nonelectric   blasting   kit.

AGO 72liBA
                                                                                               8. EXPLOSIVE                                                 ITEMS
                                                                      __ 3

                                          , D

                       • E •


                       J                                                                                                    v

           ~                                                                                  r-~
                                                                                               .'   ~',   "', .•
                                                                                                                      ~IfElT; 13:,- 'I
                                                                                                                   ~"''''       ,..     •      ""_'<0<.",
                                                                                                                                                             -~ I

                                                     Figure   1,6.   Earth rod kit.

          (a) Nonexplosive          items.
                                                                           P        100                   Point
 ldter     (Ju4ntit"               It,m                                   Q             2                 Box, cap, 50-cap capacity,
     A        1              Chest
     B                                                                                                       engineer
             1              Chamber, firing                               R
     C                                                                                  1                 Tripod
             1              Plate, base, extractor,     assy
     D       1               Rod, extension
     E       1               Extractor,  rod                                      (b)     Explosive items.
     F       1              Rod, handle and starting                      Item
     G       1              Rod, inserting                               letter    QU4ntity
     II      2               Rod, intermediate                            S         100               Charge,                earth rod,
     J       2              Rod, main, long                                                              MI2                  M44)    (w /primer,
     K     100              Adapter,    priming,    explosive,            T         100               Cap, blasting,   special, non-
                               MIA3 or MIA4                                                              electric (type I (J-1 PETN»
     L         1            Crimper, cap, M2 (w/fuse                      U           2                FU,ze, blasting, time                                50-ft coils
                               cutter)                                    V        200                Igniter, time blasting                                fuze, M2,
     M         1            Box, cap, 10-eap capacity,
                               infantry                                                                  weatherproof
                                                                          W         100
     N         2            Insulation tape, electrical, black                                            Charge, demolition, linear (two
                               adhesive cotton,  *   -inch wide                                             3-ft sections and one con-
                                                                                                            necting sleeve)

                                                                                                                                                            AGO 7258A
                                               CHAPTER   2

                                         FIRING    SYSTEMS

                           Section I. NONELECTRIC FIRING SYSTEM

42. Introduction                                     into the cap. Do not imert a~ything in~o the
                                                     cap to remove any dirt or loretgn mateTtal.
   Two types of systems for firing explosives
are in general use-electric     and nonelectric.
Both have their individual priming methods
and materials.     In addition, detonating cord
may be used with both systems to improve and
make them more efficient and effective, as de-
scribed in paragraphs 63 through 71.

43. System Components       and     Assembly
    for Detonation
   A nonelectric system is an explosive charge
prepared for detonation by means of a non-
electric blasting cap. The priming materials
consist of a nonelectric blasting cap, which
provides the shock adequate to initiate the ex-
plosive, and the time fuse, which transmits the
flame that fires the blasting cap. The assembly
of the nonelectric system follows.
   a. Cut and discard a 6-inch length from the
free end of the time fuse (A, fig. 47). Do this
to be sure that there is no chance of misfire
from a damp powder train because of the ab-
sorption of moisture from the open air. Then
cut off a minimum of 3 feet of time fuse to
check the burning rate. A more exact check
may be made by marking o'ff I-foot lengths,
timing them separately, and taking the average.
   b. Cut the time fuse long enough to permit
                                                                B. CRIMPING       ON THE       CAP
the person detonating the charge to reach a
safe distance by walking at a normal pace be-                   Figure   41.   Capping   the luse.
fore the explosion.     This cut should be made
squarely across the time fuse.
                                                       d. Hold the time fuse vertically w!th the
   c. Take one blasting cap from the cap box,
inspect it, hold it with the open end down, and      square cu t en d up and slip the blastwg cap  .
                                                      entll down over it so that the jla$h charg~ tn
shake it gently or bump the hand holding it
                                                     ~, c~p is in contact 1L'ith the end 01 the tune
against the other hand, to remove any dirt or
                                                       ::Se. i not, it may misfire. Never f.or~e the
foreign matter. Never tap the cap with a hard
                                                     I. ' f ll.~e tn t 0" tIle blasting ca}) by tWtstwg or
                                                     ttme     f .                 •
ol)ject or against a hard object.     Never blow
AGO 72tiM
     any other method. If the 'end is flattened or it
     ~s too large to enter the blasting cap freely, roll
     It between the thumb and fingers until the size
                                                                        fuse in place and thus weatherproof ..
                                                                        the joint.

     is reduced to permit free entry.
                                                                  (4) To fire, remove the safety pin, hold!
       e. After the blastingcap has been seated                        the barrel in one hand, and pull on'
  grasp the time fuse between the thumb and                            the pull ring with the other, taking uP
  third finger of the left hand and extend the                         the slack before making the final
  forefinger over the end of the cap to hold it                        strong pull. In the event of a misfire,
  firmly against the end of the time fuse. Keep                        the M60 can be. reset quickly without
  a slight pressure on the closed end of the cap                       disassembly by pushing the plunger
  with the forefinger (B, fig. 47).
                                                                      all the way in and attempting to fire
    f. Slide the second finger down the outer                         as before. (It cannot be reset under-
  edge of the blasting cap to guide the crimpers                      water, however, because. water can
  (B, fi?" 47) and thus obtain accurate crimping,                     enter the interior of the nylon case
  even In darkness.                                                   through the holes in the pull rod. The
     g. C~imp the blasting cap at a point ~ to ~
                     fuse lighter is reusable if the primer
  of an Inch from the open end. A crimp too                           is replaced.)                         .
  near the explosiL'e in the blasting cap may cause           i. Light the time fuse with a match bY
  detonation.   Point the cap out and away from            splitting the fuse at the end (fig. 48), placing
  the body during crimping.        Double-crimp the        the head of an unlighted match in the powder
. cap, if necessary, for weatherproofing.
                                                           train, and then lighting the inserted match
    Note. I( the blasting cap should remain in place       head with a flaming match or by rubbing the
 several days before firing, protect the joint between
                                                           abrasive on the match box against it.
 the cap and the time fuse with a coating of sealing
 compound or some similar substance. (As this 8ealing         Note. The M2 weatherproof     fuse lighter (fig. 39)
 compound, a 8tandard issue. does not make a water-        may be attached by sliding the fuse retainer over the
 proof seal, submerged chargeB 8hould be fired immedi-     ~nd of the fuse, firmly seating it, and applying seal-
 ately).                                                   Ing compound at the joint between the time fuse and
                                                           the lighter to retard any flash that may come from
     h. Pass the end of the time fuse through the          lighting the time fuse. In firing, hold the barrel in
  priming adapter. (The time fuse should move              one hand and pull on the pull ring with the other.
  through the adapter easily.) Then pull the cap
  into the adapter until it stops, insert into the
 cap well of the explosive, and screw the adapter
 into place. If no priming adapter is available,
 insert the capped time fuse into the cap well and
 tie it in place with a string or fasten it with
 adhesive tape or some other available material.
  (For details of nonelectric priming of demo-
 lition blocks, see para 44-46.)
    i. Attach M60 weatherproof        fuse lighter as
        (1) Unscrew the fuse holder cap two or
             three turns but do not remove. Press
             the shipping plug into the lighter to
            release the split collet (fig. 40), and
            rotate the plug as it is removed.
        (2) Insert the free end of the time fuse in
            place of the plug until it rests against
            the primer.
        (3) Tighten the cap sufficiently to hold the
                                                               Figure   48.   Lighting   time juse with match.
                                                                                                           AGO 7258A
44. Nonelectric                Priming of Demolition                         (2) Insert fused cap into hole, grasp fuse
    Blocks                                                                       with thumb and forefinger at top of
                                                                                 hole, and remove fused cap from the
  . a. ~Vith Priming Adapter. Priming adapters
                                                                                 block of explosive.
:~mphfY the priming of military explosives with                              (3) Using string approximately 40 inches
    readed cap wells. The shoulder inside one
                                                                                 in length, tie two half hitches around
~?d of the adapter is large enough to admit                                      fuse so the tie will be at the top of
 Ime fuse or detonating cord but too small for
                                                                                 the hole when reinserted.
a                               '
fit blasti ng cap. The other end of the adapter                              (4) Insert fused cap into hole and wrap
 I ~ .the internal thread of threaded cap wells in                               long end of string around the block
mlhtary explosives.      The nonelectric priming
                                                                                 of explosive a minimum of three times
~omponents are assembled as shown in figure                                      along the long axis, each time chang-
                                                                                 ing the direction of tie with a half
                                                                                 turn around the' time fuse, keeping

                 <           ~c       CRIMPERS
                                                                                 the string taut.
                                                                             (5) Tie off around the time fuse at top of
                                                                                 hole with two half hitches.
        FUSE~            ~
                                                                                    Note. Never      try to forcea  cap into an
             "                        ~~                                          expedient  fuse    well that i8 too small to
        ,            PRIMING   ADAPTER~           \                               admit it easily.
                      NONELECTRIC   BLASTING   CAP ~
                                                                        45. ,Nonelectric    Priming of M 1 Chain
                                                                             Demolition     Block
                                                                           The :M1 chain, demolition block is primed
                                                                        nonelectrically by fastening a nonelectric blast-
                                                                        ing cap at a point at least 6 inches in from one
  Figure        49.     Nonelectric    pr1mtng,       using   priming   of the free ends of the detonating chord chain
                                  adapter.                              as shown in figure 51. The explosive end 01
                                                                        the cap should point toward the demolition
. b. lVithout Priming Adapter.      \Vhen a prim-                       blocks. The firing of the blasting cap detonates
~ng adapter is not available but explosive blocks                       the cord, which in turn detonates the explosive
f~~e threaded cap wells, they are primed as                             blocks.
   ows (see method 1, fig. 50) :
                                                                        46. Nonelectric Priming of Plastic
     (1) Wrap a string tightly around the
                                                                             Explosive (C3 and C4)
          bl~ck and tie it securely leaving about
                                                                          a. The l\I5 (C3) and l\I5A1 (C4) demolition
          6 Inches of loose string on each end
                                                                        blocks with threaded cap wells or recesses and
          after making the tie (method 1 fig.
          50).                               '                          with or \vithout priming adapters and the M3
                                                                         (C3) demolition block without a threaded cap
        (2) Insert a blasting cap with fuse at-                         well are primed nonelectrically as described in
            tached into the cap well.                                   paragraph 44 and shown in figures 49 and 50.
        (3) Tie the loose string around the fuse to                        b. Plastic explosive removed from the con-
            prevent the blasting cap from being                         tainer is primed nonelectrically by molding it
            separated from the block.                                   around a fused blasting cap (fig. 52). The
   c. H'ithout Cap lVell.                                               explosive must be at least one inch thick at the
      (1) If the demolition block has no cap                            explosive end of the blasting cap and Ih inch
           well, make a hole in the end large                           thick at the sides to insure detonation.
           enough to receive the cap with a
                                                                        47. Nonelectric     Priming of Dynamite
           pointed instrument or the pointed leg
                                                                           Dynamite cartridges may be primed nonelec-
           of the crimper handle (method 2, fig.
           50).                                                         trically at either end or at the side. End prim-

AGO 72li8A                                                                                                                  55

                                                                                                    1--6IN __ /
     TIME    FUSE


                                                                    . 40 IN

                                      Figu.T~ 50. Nonelectric                   priming    withou.t   priming    adapter.


"                            FRICTION,,~,                 ,,_

                  ,,6Il      TAPE           r.., r',                                       Figure     52.   Nonelectric priming    0/   molded   plastic
~                       I    OR             I    I    I   I                                                          explosive.
                             STRING         I I       I   I
        V         /
                                            I I I
                                            ~J  ~J
                                                                                          ing is used either when a whole case is fired or
          6 IN~                                 '-'                                       when placed charges require no tamping.
                                                                                            a. End Priming Method.
                                                                                                (1) Punch a hole in the end of the car-   51.       Nonelectric  priming                0/ !Ill chain                       tridge (fig. 53).
                               demolition block.                                                (2) Insert a fused blasting cap.
S6                                                                                                                                               AGO 721i8A
      (3) T'Ie the cap and fuse securely        in the      c. Side Priming , Method        (for   Charges in
          cartridge.                                      Tamped Boreholes).
   b. ~eatherproof    Priming Method.          .               (1) Punch a hole in the cartridge about
      ( ) Unfold the wrapping at the folded                        I1h inches from one end (fig. 54).
          end of the cartridge.
                                                               (2) Point the hole so that the blasting cap
      (2) Punch a hole in the exposed dynamite.
                                                                   when inserted, will be nearly parallel,
      (3) I nser t a fused blasting cap into the
                                                                   with the side of the cartridge and the

                                                                                        .      BLASTING
                           ~CRIMPERS                                         ~                    CAP
             TIME   FUSE                                                             , IIJ                I

                                                                      B, WEATHERPROOF END PR IMING
                     A. END PRIMING METHOD

                                Figure 53. Nonelectric priming 0/ dynamite at end,

                                                                   explosive end of the cap will be at a
      ~:)     Close the ~rapping.                                  point at about half the length of the
         )   Fasten the cap and fuse securely with
      (6     a string or length of tape (fig. 53).
                                                               (3) Insert a fused blasting cap into the
         )   ~pply weatherproofing   compound to
             tie.                                                  hole.

AGO 72li8A
        (4) \Vrap a string tightly around the fuse
            and then around the cartridge, "mak-                         Then cover the string         with a water"
                                                                         repellent SUbstance.
            ing two or three turns before tying
            the string (fig. 54).                           48.   Nonelectric Priming of Ammonium
       "(5) l\foistureproof the primer by wrap-                   Nitrate and Nitramon Charges
            ping a string closely around the car-              The ammonium nitrate and nitramon chargeS
            tridge, ext"ending it an inch on each           are primed nonelectricaIly, as follows:
            side of the hole to cover it completely.           a. Place a fused blasting cap in the cap well
                                                            on the side of the container (fig. 55).
                     R/MPERS                                   b. Tie a string around the fuse and then
                                                            around the cleat above the blasting cap.
                                 ~         BLASTING           Note. A primed block of TNT placed on top of the
     TIME   FUSE    ~ .              .        CAP           charge    is recommended   to insure   positive   detonation.
                                         I              I


                                                            TIME     FUSE
                                                            :                                          ,-----J
                                                                                                       BLASTING CAP

                                                            Figure 55. Nonelectric priming 01 ammonium nitrate
                                                                          and nitramon charges.

                                                            49. Nonelectric       Priming     of Special
                                                                Charges                      .
                                                              a. .ilf2A3,   .ilf2A4,   and M3 Shaped          Charges.
                                                            These charges may be primed nonelectricaIIy bY'
Figure 5~., Nonelectric priming 01 dynamite at side.
                                                            means of a fused cap and priming adapter as
                                                                                                              AGO 725RA
A. WITH           PRIMING          ADAPTER
                                                                                                             a pull type firing device, with a nonelectric
                                                                                                             blasting cap crimped on the base, screwed into
                                                                                               M3            the cap well (fig. 57).
                                                                                             CHARGE            c. ltfl18 Demolition Charge. This charge is
                                                                                                             commonly known as sheet explosive. It is pack-
         PRIMING                   ~                                                                         aged in four sheets If&. X 3 X 12 inches, with

1TM: ::::
          O R

                  =e                      :':1   ='=====::;
                                                                                                             an adhesive on one side. It is primed by three
                                                                                                             methods (fig. 58) :
                                                                                                                  (1) By inserting and holding a nonelectric
                                                 BLASTING                                                               blasting cap in a grove or notch cut
  .          ----
            HOUT            PRIM     ----------- CAP                                                                    in the charge or
                                   ING ADAPTER                                      STRING
                                                                                                                  (2) By placing the cap between two pieces
             FRICTION              ~                          \/
               TAPE                                                                                                     of explosive or
                       OR                                          \                                              (3) By placing the cap between an overlap
:::                                                                                                                     in the charge.
                                       ' ....                          ...J

                                                                                                             50. Nonelectric Misfires
                                                                                                                a. Prevention.   Working on or near a misfire
                                                                                                             is the most hazardous of all blasting operations.
  Pigure          56                         .
                       • N onelectnc " prtmtng                     of shaped charges.                        A misfire should be extremely rare if these pro-
                                                                                                             cedures are followed closely:
Shown in fi                                                                                                        (1) Prepare all primers properly.
available gure ?6. If a priming adapter is not
by.'         the prImer may be held in the cap well                                                                (2) Load charges carefully.
     a strIng or friction tape.                                                                                    (3) Place primer properly.
   b. Bangal          T orpedo. The bangalore tor-                                                                 (4) Perform any tamping operation with
ped o may b         .                                                                                                  care to avoid damage to an otherwise
tirn f         e prImed by assembling a length of
                                                                                                                       carefully prepared charge.
pri~. use and a nonelectric blasting cap in a
                                                                                                                   (5) Fire the charge according to the
into ~~g adapter and screwing the assembly
                                                                                                                       proper technique.
A secre cap well of a torpedo section (fig. 57).
                                                                                                                   (6) If possible, use dual firing systems
        Ion may also be primed nonelectricaIIy by

                                                        R                             I
                                                                                                                                 BANGALORE   TORPEDO

  ::::     TIME         FUSE                        ~
                                                                   , E3n                     --            DJ--~~~---[D
                                         ~~~~I~~R"7                                    ~

                                                                                                  l      NON ELEl.-c-r-R-1

                                                                                                         BLASTING       CAP

                                                            '~\                                PROTECTIVE         CAP
                         MI PULL
                          FIRING                            \O~                 .      ~(ALWAYS              REMOVE)


                                                 ~Xr~O~                              0"             _'     to-",--========~~                             DJ
                                                    Figure                    57.    Nonelectric     priming     of bangalore   torpedo.

AGO      72Ci8A                                                                                                                                             S9
                                                CRIMPERS                                         at least 30 minutes after the expecJ
                                                                                                 time of detonation.    This should b~
                                                                  EXPLOSIVE                      ample time for any delayed exploslO,.r
                                                                        I                                                            •
                                                                                                 to take place because of a defectl""E


                                              ,[                  I
                                                                              ]                  powder train in the fuse. Under cer~
                                                                                                 tain combat conditions, however, iIl1
                     BLASTING   CAP
                                                                                                 mediate investigation may be neceS
                                                                                                 sary.                                 J,
            (I)                                                                          (2)
                  CUT NOTCH         IN                                                           If the misfired charge is not tampe ~
                  EXPLOSIVE,        INSERT                                                      lay a new primer at the side of the
                  CAP, AND FASTEN
                  WITH STRING OR
                  FRICTION  TAPE; OR
                                                     E                        J                 charge, without moving or disturbin'I .
                                                                                                it, and fire.
                                                                                        (3) If the misfired charge has no mor~


                                                                                                than a foot of tamping, attempt t
                                                                                               explode it by detonating a new 2-poun I     d
                                                                                               primer placed on top.                 .~
          (2)     FASTEN   ON TOP WITH
                                                                                                If the misfired charge is located in       j
                  PIECE OF SHEET                                                               tamped borehole, or if the tampe,
                  EXPLOSIVE;   OR                                                              charge is so situated as to make~

          (:3)    LAP ONE END OVER
                                                     IDf3 - --.
                                                                                               method (3) above impractical,
                                                                                               move the tamping         by means 0,
                                                                                               wooden or nonmetallic tools. A void~
                                                                                               accidentally digging into the charge.,
                  ANOTHER  WITH CAP                                                            Also, the tamping may be blown out,
                  INSERTED  BETWEEN
                                                     [                                         by means of a stream of compressed ..
                                                                                               air or water if either is available .•
                                                                                               Constant checking of the depth of the .
                                                                                              borehole from the ground surface or .
                                                                                              the top of the charge during digging.
       Figure       58.   Nonelectric      priming    0/ sheet explosive.                     will minimize the danger of striking             1

                                                                                              the charge.      When the charge haS .
                                                                                              been uncovered within 1 foot, insert ~
                     (para 72-75).     If both systems are                                    and detonate a new 2-pound primer. ~
                     properly assembled, the possibility of                            (5) An alternate method of reaching ~~
                     a misfire is reduced to a minimum.                                       deep misfired charge is to drill a neW~
        b. The l/andling 01 Nonelectric Jt!isfires. Oc-                                       hole within one foot/of the old one ~
     casionally, despite all painstaking     efforts, a                                       and to the same depth.       A 2-pound 4
     nonelectric misfire will occur.    Inv(stigation                                         primed charge is then placed in the.
     and correction should be undertaken only by the                                          new hole to detonate the misfired.
     man that placed the charge.       For a charge                                          charge. Extreme care is required in 4
     primed with a nonelectric cap and time fuse, the                                        drilling the new hole to avoid striking
     procedure is as follows:                                                                the old misfired charge or placing the
          (1) Delay the investigation of the misfire                                       . new charge too far away to induce

                                                    SECTION       II.   ELECTRIC FIRING SYSTEM
     51. Components and Assembly for
         Detonation                                                               tric spark or impulse to initiate detonation.
       The electric firing system provides the elec-                              The electric impulse travels from the power
                                                                                  source through the lead wires to fire the cap.
                                                                                                                            AGO   72FiSA
                                                                    The chief components of the system are th€
                                                                    blasting cap, firing wire and reel, and the
                                                                    blasting machine. The preparation of the ex-
                                                                    plosive charge for detonation by electrical
                                                                    means is called electric priming.          Priming
                                                                    methods are described below.
                                                                       a. Testing the Cap.
                                                                          (1) Test the galvanometer (para 36) (fig.
                                                                          (2) Remove the short circuit shunt (pre-
                                                                               vents accidential firing) from the
                                                                               lead wires of the electric blasting cap
                                                      SHOW                      (fig. 60).
                                                      WIDE                (3) Touch one cap lead wire to one gal-
                                                DEFLECTION                     vonmeter post and the other cap lead
                                                 NEEDLE                        wire to the other. If the instrument
                                                                               registers a flowing current, the blast-
                                                                               ing cap is satisfactory;    if not, the
                                                                               cap is defective and should not be
                                                                               used. During the test, always point
                                                                               the explosive end of the blasting cap
                                                                               away from the body.
                                                                       b. Placing the Cap in the Explosive.
                                                                          (1) Pass the lead wires through the slot
                                                                               of the adapter and pull the cap into
                                                                               place in the adapter.
                                                                          (2) Insert the cap into the cap well of the
                                                                               explosive and screw the adapter into
                                                                          (3) If a priming adapter is not available,
                                                                               insert the electric cap into the cap
         Figure   59.   Testing   the galvauometer.

                                      Figure   60.     Assembling   the electric   primer.
AGO 72li8A

               TW   o    HALF
                            OR   HITCHES

                    GIRTH       HITCH

                                               Figure   61.   Electric   pnmm g without
                                                                           . .              adapter.

                                . the lead wires around .the
              well and be h If hitches or a gIrth                                              .                       .      Blasting
              block by two a For details of elec-                                        electrical                   nufacturer maY
                                                                                                         ch ar acterisbcs.
                                                                                         caps of the same ma            I color of the
              tric (.fi~. 61~f d~molition blocks, see
                                                                                         be identified by theh~a~~~nt. This .i~
              para 53.)                                                                  cap, or shape of t f the M6 spe~I8
                                                                                         not true, however, 0       II of whlc~
        Wire Connectiolls.    lead wires and ~he                                                    It'
     c. (1) Bare the. two ~a~he ends and splIce                                          electric bas m g. caps-a same specI"
                                                                                         are made accordIng to
            firing wIres a     form two connec-
            them together52,~ofig. 62). Insulate                                   (
                                                                                         fication.                 .        fety rea-
                   (para                                                            2)   Firing                  'dual should be
                                                                                                the c'trc~'td" For sa
                                                                                                      .     't
            tions . friction tape.
                                                                                         sons, on y                      .
                                                                                                          In t IVI blastmg ma"
            Check again .'
        (2) these wIth. 'Vlth the galvonmeter, a                                         detailed to con?ec ircuit and to fire
              (3), above.           nds of the firing                                    chine to ~he firmg ~Id be responsi~le
                                                                                         the cirCUIt. He sho bl ting machme
              Fasten the two free ~
 on the blasting
          (3) wIre to the two pos

                                                                                         for the care of. t~\1 ::ing activities.
              machine.                                                                   at all times durmg 'tha r connect the
                                                                                         He also should el e. it or check
     d Precautions.                     aps.      If two or more                                     .   . the CIrcu       .    1
                                                                                         blasting wlre~ mby on-the-spot VISUS
                                                                                         their connectIon
      •            or more c
                    '0             .  caps are con-
          (1) Tw .    .litary blastm!1 . b sure                                          examination.
              specIal ml                ame cIrcUIt,           e
              nected in the s de by the same man-
              that they ar~:a is essential to pre;                          52     Splicing Electric Wires ..       must have
              ufacturer.     IS blasting caps 0                                  •          .
                                                                                 Insulated WIres, before .splIcmg, the en ds,
                                                                                                              d from
              ve nt misfires, as
              qifferent ma nufacturers
                                       have different
                                                   .                                    .
                                                                            the insulating m aterial stnppe wire (fi g. 62).
                                                                                               . h      f bare
                                                                                  . g about 3 Inc es 0
                                                                            exposm                                           AGO "'sA
                                                                                 All enamel also must be removed from the
                                                                                 bared ends by carefully scraping them 'with
                                                                                 the back of a knife blade or other suitable
                                                                                 tool, but not nicking, cutting, or weakening
                                                                                 them. Stranded wires, after scraping, should
                                                                                 be twisted tightly .
.!.!l_                                                                              a. Two Wires. Two wires, having been pre-
           _______________                                               -       pared as described above, may be spliced as
                                                                                 shown in figure 62. This is called the \Vestern
                                                                                 Union "pigtail" splice.
                                                                                    b. Two Pairs of lVires. Join one pair of
                                                                                 electrical conductors to another pair by splic-
                                                                                 ing the individual wires to one another (one
                                                                                 of one pair to one of another pair, and the
                                                                                 second of one pair to the second of the other).
                                                                                 In order to prevent a short circuit at the point
                                                                                 of splice, stagger the two separate splices and
                                       ______                      --            tie with twine or tape as in (1), figure 63. An
                                                                                 alternate method of preventing a short circuit
                                                                                 at the point of splice is shown in (2), figure
                                                                                 63, where the splices are separated,         not
lil__                                                                               c. Protection of Splices. protect all bare wire
                   __________                                            -       splices in wiring circuits to prevent their short-
                                                                                 circuiting to the ground or to each other. \Vhen-
                                                                                 ever possible, insulate them from the ground or
                                                                                 other conductors by wrapping them with fric-
.,>--                                                                        ;
                                                                                 tion tape or other electric insulating tape. This
                                                                                 is particularly    necessary when splices are'
                                                                                 placed under wet tamping. Circuit splices, not
                                                                                 taped or insulated, lying on moist ground, must
  Figure    62.
                    Splicing    two wires (Western               Union           be supported on rocks, blocks, or sticks so that
                         "pigtail"  splice).                                     only the insulated portion of the wires touches
                                                                                 the ground. They may be protected from dam-
                                                                                 age from pull by typing the ends in an over-
     CAP     WIRE                                                                hand knot, allowing sufficient length for easy
~.                        ~       TWIN.. E.     . OUTSIDE
                                                                                 splicing «1), fig. 62».
                                 -~                                              53. Electric Priming of Demolition       Blocks
 (II                                                                     III      . a. Blocks with Threaded Cap lVells.
                                                                                       (1) lVith priming adapter. Priming adapt-
                                       FIRING    WIRE                                      ers simplify the priming of military
                                                                                           explosives with threaded cap wells. A
                                                                                           slot running the full length ofT the
                                                                                           adapter is provided for easy insertion
                                                                                           of the lead wires. The end of the
                                                                                           adapter that secures the cap fits the
                                                                                           internal thread of threaded cap wells
                                                                                           in military explosives. The priming
                                                                                           components are assembled as shown in
                                                                                          figure 64.
       Figure     6.'1.                         .
                              Splicin g t wo putrs        .
                                                     0/ wtres.
AGO 7268A



                                     ~'Dm                                               ..


                     Figure   6-'.     Electric   priming     of demolition    block with priming          adapter.

       (2) lVithout priming adapter. If a prim-
           ing adapter is not available and the
           demolition block has a threaded cap
           well, insert the electric cap into the
           cap well and tie the lead wires around
           the block by two half-hitches or a girth
           hitch. Leave a small portion of slack
           wire between the blasting cap and the
           tie to prevent any pull on the blasting                                POINTED
           cap (fig. 61).
    b. Blocks lVithout Cap lVells. If the demo-
lition blocks have no threaded cap wells proceed                              ~SHUNT               ~
as follows:                                  .                                Il!:IREMOV~              •     \
       (1) :Make a hole in the end large enough
           to receive the cap with a pointed non-                                       ~RIC
           spark instrument or the pointed leg of                       ~~ifJ~CAP
           the crimper handle (fig. 65).
       (2) Insert the cap in this cap well and tie                                                           TWO HALF' HITCHES
           the cap wires around the block by two                                                                    OR
           half hitches or a girth hitch. To pre-                                                             GIRTH HITCH
           vent pull on the cap, always leave a
           small portion of slack wire between
           the blasting cap and the tie.
             Note. Never try to force a blaBting cap
          into an expedient fUBt! well that iB too Bmall
          to admit it eaBily.

54. Electric Priming of M 1 Chain
    Demolition Block
  The :M1chain demolition block is primed elec-                            Figure     65.    Electric priming of pla'stic explosive       j
                                                                                                 without cap well.                        !
64                                                                                                                                        i
                                                                                                                             AGO 72lisA
                                                                         (3) Tie the lead wires around the car-
trically b           '
to one f y fastenIng an electric blasting cap                                tridge with two half hitches.
ChaI'n 0, the free ends of the detonating cord                        b. Side Priming Jlclethod.
rneth dwIth f'rIctIon tape or by some other                            . (1) Punch a hole in the cartridge about
POintOt' The explosive end of the cap should                                 11/~ inches from one end (fig. 68).
firing o~ard the chain demolition blocks. The                            (2) Point the hole so that the electric
Which ~ tthe blasting cap detonates the cord,                                blasting cap, when inserted, will be
S          n urn detonates the entire chain.                                 nearly parallel with the side of the
    S. Electric P'rlmang
                      .              of Plastic    Explosives                cartridge and the explosive end of the
       (C3 an d C4)                                                          cap will be at a point at about half the
   a, The M5 (C 3) and M5A1 (C4) demolition                                  length of the cartridge.
blocks'                                                                  (3) Insert the blasting cap into the hole.
with wIth threaded cap wells or recesses and
                                                                         (4) Tie the lead wires around the car-
 (C3) a~~ wi~~out priming adapters and the M3                                tridge with two half hitches or fasten
Well          o~Ihon block without a threaded cap
                                                                             with a string or
graphare Prim e d e IectrIcally as shown in para-
   b PI ~nd figures 61, 64, and 65,                                 51. Electric Priming of Ammonium Nitrate
    .                     .
tainer ashc ex p IOSIve removed from the con-
         is        .                                                     and Nitramon Charges
around the ~~Im~d electrically by molding it                          The electric blasting cap is placed in the cap
rnust extend ashng ca~ (fig. 66). The explosive                     well and the lead wires are looped around the
of the bl       . at least 1 Inch at the explosive end
                                                                    cleat (fig. 69).
InSure d ashng . cap an d I' Inch at the SIdes to
            t                   /2 .             .
          e onahon.                                                 58. Electric Priming of Special Charges
                                                                       a. llf2AS,. llI2A4, and 1llS Shaped Charges.
                                                                    These may be primed electrically by means of
                                                                    an electric blasting cap and a priming adapter
                                                                    as shown in figure 70. If a priming adapter is
                                                                    not available, the electric cap may be held in
                                                                    place by a length of string or friction tape.
                                                                       b. Bangalore Torpedo. The bangalore tor-
                                                                    pedo may be primed electrically by assembling
                                                                    a blasting cap and priming adapter and screw-
                                                                    ing the assembly into the cap well of a torpedo
                                                                    section (fig. 71),
                                                                       c. JlcIl18 Demolition Charge. This charge,
                                                                    commonly known as sheet explosive (fig. 72),
                                                                    is packaged in four sheets 1,4 x 3 x 12 inches,
                                                                    with an adhesive on one side. It is primed by-
                                                                          (1) Inserting      and holding an electric
     Figure    66.    Electric      priming   of molded   plastic
                                                                                 blasting cap in a groove or notch cut
                                 explosive.                                      in the charge, or
                                                                          (2) Placing the cap between two sheets or
56. Electric P'rlmang of Dynamite
                       .                                                         pieces of explosive or,
   D"       .                                                             (3) Placing the cap between an overlap of
       namite ' car t'd ges may be primed elec-
trically t
                                                                              the charge.
ing is u:edeI~her end or at the side. End prim-
When pI       eIther when a whole case is fired or                  59. Series Circuits
   a. E ~ced ~h~rges require no tamping.                               a. Common Series.     This is used for con-
       (1~ Pr1,mtng IIIethod.                                       necting two or more charges fired electrically
           P~nch a hole in the end of the car-                      by a blasting machine (fig. 73). A common
           trIdge (fig. 67).                                        series circuit is prepared by connecting one
       (2) Insert an e I'             .
                         ectric blastmg cap.
AGO 7208A

      323-S6\ 0 • 68 • S

                          t.--            ---;:::={

                                 Figure    67.    Electric   priming        of dynamite   at end.

                                 @         ELECTRIC
                         BLASTING                                                           .
     GALVANOMETER                                            --~---------_.

                                 Figure    68.    Electric   priming        of dynamite   at side.

blasting cap lead wire from the first charge to
                                                                       distance ~etween blasting caps is greater thaIl
one lead wire in the second charge and so on
                                                                       the length of the usual cap lead wires.
until only two end wires are free, then con-
                                                                          b. "Leapfrog"     Series.     The    "leapfrog"
necting the free ends of the cap lead wires to
                                                                       method of connecting caps in series (fig. 73) is
the ends of the firing wire. Connecting wires
                                                                       useful for firing ditching charges or any long
 (usually annunicator wire) are used when the
           ,                                                           line of charges. It consists of omitting alternate
                                                                                                                AGO 72&8.'\
                                                                         charges on the way and then connecting them
                                                                         to forma return path for the electric impulse
                                                                         to reach the other lead of the firing wire. This
                                                 -:~ ..ELECTRIC
                                                       : BLASTING        brings both end wires out at the same end of
                                                       : CAP             the line of charges, and thus eliminates laying
                                                                         a long return lead from the far end of the line
                                                                         of charges back to the firing wire.

                                                                         60. Testing Electric Wires and Circuits
                                                                            a. Firing ~Vires 'ftlay be Tested as Follows:
                                                                                (1) Check galvanometer        by holding a
                                                                                    piece of metal across its terminals
                                                                                    (para 36; fig. 59).
                                                                                (2) Separate the firing wire at both ends,
                                                                                    and touch those at one end to the
     FASTEN        WIRES        ~,                                                  galvanometer posts. The needle should
                                                                                    not move. If it does, the firing wire
                                                                                    has a short circuit (fig. 74) ; or
                                                                                (3) Twist the wires together at one end
                                                                                    and touch those at the other to the gal.
                   CAP                                                              vanometer posts .. This should cause a
                                                                                    wide deflection in the needle. (See
                                                                                    note at end of c (2), below). No move.
                                                                                    ment of the needle indicates a break.;
                                                                                    a slight movement, a point of high re.
                                                                                        Note. Firing wire may be tested on the
                                                                                     reel, but should be testrd again after un-
•   Figure   69.
                                                                                     reeling, 'Which may separate broken wires
                    Electric pr"tmtng 0f ammomum       nitrate   and                 unnoticed 'When reeled.
                            nitramon charges.

                                                                       REMOVED @


                                                                                           FRICTION      ~   OR
                                                 I                                               TAPE ~


                                        Figure   70.     Electric   priming   of shaped charges.
                                                              =-E3J.\          ~tm~~gl
                                                                                            tG_---...;.oJ ~__
                                                                                                         BANGALORE    TORPEDO
                                              REMOVED                PRIMING


                                              Figure    71.    Electric   priming    0/ bangalore   torpedo.

                                                           SHEET                      c. The Entire Circuit May be Tested as Fo~ .
                     A     SHUNT                         EXPLOSIVE                  lows:
                    @f    REMOVED                                I
                                                                                         (1) Splice firing wires to series circuit

         ELECTR IC
      BLASTING       CAP
                           '7 ~ ~_,--
                                                                                              and move to firing position.
                                                                                         (2) Touch free ends of firing wire to gal ..
                                                                                              vanometer posts (fig. 76). This should
(I)     CUT


====E=X PL_O=S=I_V-:...E
                __ I_N~~_;R_T_-J)

               STRING OR

                                               == ]
                                                                                              cause a wide deflection of the needle.
                                                                                              If not, the circuit is defective. If de"
                                                                                              fective, shunt wires. Then go down
                                                                                              range and recheck the circuit, repeat ..
                                                                                              ing a(2), (3) and b(l), (2) above. If
        FRICTION   TAPE; OR                                   TIE
                                                       /STRING                                a splice is found defective, resplice the
                                                                                              wires.    If a cap is found defective,

                                                                                              replace it. Then test the entire circuit
                                                                                              again to make sure that all breaks
                                                                                            . have been located before attempting
        EXPLOSIVE:   OR                                                                       to fire the charge.
                                                                                                Note. To get a "wide deflection of the

---==43-J                                                                                     needle" the galvanometer battery should be
                                                                                              in good condition.

                                                                                    61. Electric Misfires
(3)    LAP ONE           END OVER
       ANOTHER           WITH CAP                                                      a. Prevention of Electric :fltfisjires. In order
       INSERTED           BETWEEN                                                   to prevent misfires, make one demolition spe"
                                                                                    cialist responsible for all electrical wiring in a
                                                                                    demolition circuit. He should do all splicing to
                                                                                    be sure that-

  Figure      72.    Electric       priming    0/   8heet expl08h'e.
                                                                                         (1) All blasting caps are included in the
                                                                                             firing circuit.
                                                                                         (2) All connections between blasting cap
      b. Series Circuits },[ay be Tested as Follows:
                                                                                             wires, connecting wires, and firing
          (1) Connect charges as shown in figure 75.                                         wires are properly made.
        . (2) Touch the free ends of the lead wires                                      (3) Short circuits are avoided .
              to the galvanometer posts. This should                                     (4) Grounds are avoided.
              cause a wide deflection of the needle.
                                                                                         (5) The number        of blasting   caps in any
                                                                                                                                 AGO 72r.IIA
A. COMMON                                                        UNINSULATED   PORTIONS OF WIRES
   SERIES                                                        SEPARATED   AT BOTH ENDS


                                                                 UNINSULATED  PORTIONS          OF WIRES
                                                                 TWISTED TOGETHER   AT          ONE END~

B.   I'

                                                                   SATISFACTORY              DEFECTIVE

                                                                            Figure   74.   Testing   firing   wire.

                                                                       (3) Defective and damaged connections,
                                                                           causing either a short circuit, a break
                                                                           in the circuit, or high resistance with
                Figure   79 •   S' er'les    .    .
                                                                           resulting low current.
                                                                       (4) Faulty blasting cap.
              circ.uit does not exceed the rated ca-                   (5) The use in the same circuit of old type
     U. C     paclty of the power source on hand.                          (J-2) special blasting caps made by
Clfiecauause of El ec t'nc Mtsfires. Common spe-
                                .                                          different manufacturers.
       1) ses of ele ct'fIe mIsfires inc1ude-                          (6) The use of more blasting caps than the
      (     Inoper a t'lve or weak blasting machine                        power source rating permits.
          (2) ~r power source.                                      c. Handling Electric J./isjircs. Because of the
               mproperly-operated             blasting machine    hazards of burning charges and delayed ex-
              or power source.
AGO 725M.
      plosions, electric misfires must be handled with
      extreme caution. A burning charge may Occur
                                                                   is not dual-primed, investigate immediately.    If
                                                                   the system is below ground and not dual-primed.
      with the use of electric as well as nonelectric
                                                                   proceed as follows-                               I
      caps. Misfires of charges primed with deto-
      nating cord fired by electric blasting caps are                    (1) Check the firing wire connection to the~
      handled as described in paragraph 71. If the                           blasting machine or power sourc~
      charge is dual-primed electrically and below                           terminals to be sure that the contaet~..
      ground, wait 30 minutes before investigating to                        are good.                               I
      make sure that the charge is not burning; or if                   (2) Make two or three more attempts                ,.
      dual-primed above ground, wait 30 minutes be-                          fire the circuits.
      fore investigating.    On the other hand, if the                  (3) Attempt to fire again, using another
      electric misfire is above ground and the charge                        blasting machine or power source.              I
                                                                        (4) Disconnect the blasting machine firing'



                                                                                       SATI SFACTORY

                                       Figure     '/5.    Testing a series circuit.

                                                                                DEFECTIVE              SATISFACTORY

                                      Figure    '/6.     Testing the entire circuit.
                                                                                                                AGO 725SA   I
                                                                     ing even under the most adverse conditions.
                    wire and wait 30 minutes before fur-             Mobile type transmitters are prohibited within
                    ther investigation.      Before moving on        150 feet of any electric blasting caps or elec-
                    to the charge site be sure that the              trical blasting system. If blasting distances are
                    fi rIng wires at the ' power source end
                                                                     less than those shown in table VII, the only safe
                    of t~e circuit are shunted to avoid any          procedure is to use a nonelectric system, which
            (5)     possIble static electric detonation.             cannot be prematurely detonated by RF cur-
                    Ch.eck the entire circuit, including the         rents. If, however, the use of the electric sys-
                    fir~ng wire, for breaks and short cir-           tem is necessary, follow precautions given in
            (6)     If the fault is not above ground, re-            AR 385-63.
                    ~ove the tamping material very care-                  Table VII.      Minimum Sale Distance lor RF
                    . ully from the borehole to avoid strik-                                 Transmitters
            (7)     Ing the electric blasting cap.                                           Fixed transmitters
                    M~ke no attempt to remove either the                                                          Minimum
                    r;Imer or the charge.                                   Tran8mitt~r   power   (watill).         ( ft.)

            (8)            the fault is not located by the re-                                                     100
                    ~oval of the tamping material to with-                                 5-25
                    In 1 foot of the charge place a new                                                            220
                    e I.l                         '
                       ectric. prImer and 2 pounds of ex-                                                          350
            (9)     P ?SIVe at this point.                                              250-500
                    ~Isco~n~ct the blasting cap wires of                                600-1,000
           (10)         e OrIgInal primer from the circuit.                                                       1500
                    Connect th e WIres of the new prImer
                    .                                     .                                                       2200
                                                                                    , 5,000-10,000
                    In their place.                                                                               3500
           (11)     Re.pI                                                                                         5000
           (12)              .ace the tamping material.                              25,000-50,000
                    InItIate detonation.      Detonation of the                      50,000-100,000
                    new. prImer wIll fire the original
                    charge.                                             b. Lightning.   Lightning is a hazard to both
                    de'~ote. In some cases It may be more
                               b                                     electric and nonelectric blasting charges.      A
                    with' Ie or expe d'lent to   drill a new hole    strike or a nearby miss is almost certain to ini-
                     In      a foot of the old   one at the same
                    d epthh to av'd accIdental
                                        .                            tiate either type of circuit. Lightning strikes,
                    old           01             detonation of the
                    2 C arge and then place      and prime a new     even at remote locations, may cause extremely
                     -pound charge.                                  high local earth currents and shock waves that
 62.        Premat     D                                             may initiate electrical firing circuits. The ef-
            Cur    ure   etonation          by    Induced
                                                                     fects of remote lightning strikes are multiplied
       a    I rents and Lightning
                                                                     by proximity to conducting elements, such as
 tion. of el t. Currents. The premature detona-                      those found in buildings, fences, railroads,
 f requency ec rlC blast. Ing caps b y Induced radIO
              (RF                      .             .
                                                                     bridges, streams, and underground cables or
 showing the ) .c~rrent is possible. Table VII,                      conduit. Thus, the only safe procedure is to
 transmitt        mInImum safe distance versus                       suspend all blasting activities during electrical
 Yond Which     power ' In d'Icates the distance be-
            er it .       .
                  IS safe to conduct electrical blast-               'storms.

                                        Section III.     DETONATING       CORD PRIMING
 63         Components                                               tiating system may remain above the water or
    a. Of all.          .                                            ground.
  ~ating cordPr:mers for explosive charges, deto-                       b. The detonating cord primer consists, gen-
  In many          probably the most versatile and                   erally, of a length of detonating cord and the
            cases the      t      . .             .
, especially ap r      mos easIly Installed.   It IS                 means of detonation which may be an electric
. grOund bla ? Icable for underwater and under-                      blasting cap initiated by a blasting machine or
              stIng, as the blasting cap of the ini-
 AGO       721i8A
power source or a nonelectric blasting cap ini-
tiated by a fuse lighter and a length of time                                nating cord at an angle across the
fuse. The blasting cap of either the electric or                             explosive block as shown in A, figure
nonelectric system is attached to the free end
of the detonating cord by means of a length of                          (2) Wrap the running end three timeS
string, wire, or friction tape. Detonating cord                              over the end laid at an angle and
primers are usually tied around the explosive                                around the block, and on the fourtb
block; however, in situations where a close                                  turn, slip the running end under the
contact between the explosive block and the                                  three wraps parallel with the other
target is required, a nonelectric blasting cap is                            end and then draw tight.
crimped on the end of the detonating cord and                           (3) Attach an electric or nonelectric firing
placed in the cap well.                                                      system.
                                                                     b. Alternate Method No.1 (B, fig. 77).
64. Priming Demolition            Blocks                                (1) Tie the detonating cord around the
     a. Common Jfethod   (A, fig. 77)
                                                                             explosive block (on top of the booster,
                                                                             if present) with a clove hitch with twO
       (1) Lay one end of a 4-foot length of deto-
                                                                             extra turns as shown in B, figure 7~..,

                                                                   c.    ALTERNATE       NO.2

                         Figure     77.    Detonating   cord   priming    0/'   demolition   blocks.

          The cord must fit snugly against the
          blocks and the loops be pushed close                           (2) Attach an electric or nonelectric firing'

                                                                                                             AGO 7268ft.
  c. (1) p~ate Method No.2 (C, fig. 77)
     Alter                                                                   cord running lengthwise through the individual
                                                                             blocks.- If an additional length of detonating
             ace a loop of detonating cord on the
                                                                             cord is required, it is conn~cted to the deto-
     (2) expl OSlve block as in C, figure 77.                                nating cord of the chain with a clip or square
          'Vrap the detonating cord four times
                                                                             knot. The additional length of detonating cord
          around the block and finally draw the
                                                                             may be initiated by means of an electric blast-
     (3) ru nning end through the loop.
                                                                             ing cap and firing device or an nonelectric blast-
           Pull until tight.
     (4) Attach an electric or nonelectric firing                            ing cap, length of time fuse, and a fuse lighter.
          system.                                                            If the cord running through the blocks is cut
              l!'l0te. This alternate method is more ap-                     too closely to the end block to permit such a
             p lcable to short than to long detonating                       connection, the additional length of detonating
             cord branch lines or primers.                                   cord may be fastened by a clove hitch with two
65. Primin 9 M 1 Cham Demolition Block
                          .                                                  extra turns near the end of the block over the
     e Ml chain d emo l't' IOn block has detonating
                       I                                                     booster    (fig. 78).

                                                                                        f1i                                                .r,lL,
                                                                                                                                            I I
                                                                                                                                            I I
                                                                                                                                                            I I
                                                                                                                                                            I I

                                                                         .                           ELECTRIC
                                                                                                                                               l II I:
                                                                                                     BLASTING                                               I        I
                                                                                                     CAP'                                      l I I                 I
                                                                        DETONATING                                                             "'IT'"       LIT'"
                                                                          CORD                                                   ~~::&1II'1I                     ~-lllt.

 ____                                                                                      __\      GIN                   CLIP

          --             cc;o----------------------                                DETONATING         CORD

                                                                                                                        SINGLE             BLOCK

 ____                                                                              CLOVE HITCH WITH
  C. N                                                                             TWO EXTRA TURNS
         ONELECTR   IC                  ------------------   ;;,-...:                                                                              I ,-,         ,
                                                              ~     CRIMPERS             NONELECTRIC                                           rl~ r-'
                                                                                         BLASTING                                              I I I I
                                                                                                                                               I I I I

                                                                             L----        CAP                                                  I
                                                                                                                                               I     I
                                                                                                                                                     I     I
                                                                                                                                               I           I I

                                                                              f!jCLIP                                        \""-'

                         Figure   78.      Detonating         cord priming     01 Ml    chain    demolition    block.

66. Pri ·                                                                    and securing        it with a knot or by lacing as
   F      mtng Dynamite
   . or of tchieft y In boreholes, ditching, or re-
         use         .                                                       shown in figure 79.
 the deton st~mps, dynamite is primed by lacing                              67. Priming         Plastic      Explosive     (C3 and                              C4)
 PUnching a t~g cord through it. This is done by                                Compositions C3 and C4 when removed from
,_through the ree or .four equally-spaced holes                              the package are primed with detonating cord,
 detonaf        dynamIte cartridge, running the
          Ing cord back and forth through them,                              as follows:
AGO 72liSA

               ELECTRIC OR
               NON ELECTRIC


Figure    '19. Detonating   cord priming   01 dynamite.

   a. Take a 10-inch bight at the end of the
detonating cord and tie an overhand knot (fig.
   b. Mold the explosive around the knot, leav-
ing at least Ih inch of explosive on all sides and
at least 1 inch on each end .
  . Note. Another method is to cut the block longitu-
dinally, then insert the knot, and fasten with tape or
string as shown in figure 80.

68. Priming Ammonium              Nitrate and
    Nitramon Charges
                                                           Figure   80.   Detonating    cord   01 plastic
   To prime ammonium nitrate and nitramon
cratering charges with detonating cord:
   a. Pass the detonating cord through the tun-
nel provided on the one side of the can (fig. 81).        69. Priming Special         Charges
   b. Tie an overhand knot on the portion                    a. Shaped Charges.    M2A3 and M3 shaped
passed through about 6 inches from the end.               charges are primed with a length of detonating
   c. Attach an electric or nonelectric firing sys-       cord with a nonelectric blasting cap crimped 011
tem (fig. 81).                                            (fig. 82)" and detonated with an electric or non"
   d. For dual priming any firing system may              electric firing system.
be used for the additional charge-a        I-pound
                                                             b. Bangalore Torpedo. A bangalore torpedO
block of TNT-to         insure detonation     (para
                                                          may be primed by attaching a length of deto"
21c) •
                                                          nating cord by wrapping six turns directly over
                                                                                                            AGO noS}.

                                                     CORD                                         OR

---    TRIC INITIATOO---------------------
 B. ELEC---

                Figure   81.   Detonating      cord priming   0/   ammonium        nitrate   and nitramo        charges.


                                                                                 ~                          PRIMING
__                                                                         GIN                              ADAPTER

   N --__              DETONATING        CORD
B. p~NELECTRICWITH------------------------                         ~

          IMING ADAPTER?                                           ~          ~

~';-IME                           FUSE             ~                                                    C;J

                               Figure    82.    Detonating    cord priming        0/   shaped charge.
AGO 7268A
                                        ~                .
                                                                                ATTACHWITH FRICTIONTAPE
                          CRIMPERS',         ~                                  OR LENGTH OF STRING


a=tFJ_.- -5 }
~   EL.EcTRIC------~LECTR~------------------------

                                                                                                       SIX   TURNS

                           Figure   83.     Detonating       cord priming   0/ bangalore   torpedo.

the booster (fig. 83) and detonating with an
                                                                               The free end of the detonating cord is 11
electric or nonelectric firing system.
                                                                               fastened to the main line by a clip or
   c. Pole Charges. Detonating cord assemblies

                                                                               a square knot as shown in figure 85.
are excellent primers for pole charges, as the
                                                                          (4) Advantages.       Many advantages maY.
detonating cord spans the distance from the
                                                                               be gained by th euse of these primers .~
charge to a position where the electric or non-
                                                                               -they     may be made up in advance, ..
electric firing system is accessible to the blaster.
                                                                               thus saving time at the target, which ~
The method of priming with a dual electric
                                                                                is a great advantage when 'time is a ~
primer is shown in figure 84.
                                                                                critical factor j and they permit the I
70. Assemblies and Connections                                                 person in charge to attach the initiat"4
                                                                                ing system and function it as he de" .
  a. Detonating Assemblies.
                                                                                sires, giving him complete control of •
     (1) Nonelectric.     This detonating assemb-
                                                                                the operation.      Also, a detonating.
          ly consists of a length of detonating
                                                                                cord loop is useful in attaching two or ~
          cord (approximately      2 feet), a non-
                                                                                or more ring mains to a single prim .. I
          electric blasting cap, a length of time
                                                                                ing assembly; and a single electric or 1
          fuse, and a fuse lighter. The blasting
                                                                                nonelectric 'blasting cap properly fast .. i
          cap is crimped to the time fuse and
                                                                                ened to two detonating cord mains bY
          then fastened to the detonating cord
                                                                                a string, wire, or piece of cloth win
           (A, fig. 85). The fuse lighter is then                             . detonate both (fig. 86).        ,.1
          fastened to the time fuse. The length
                                                                        b. Detonating Cord Connections. A detonat ..
          of time fuse depends on the time. re-                      ing cord clip (fig. 26) or square knot pulled
          quired for the blaster to reach safety                     tight is used to splice the ends of the detonat ..
          after lighting the fuse.
                                                                     ing cord. At least a 6-inch length should be left
      (2) Electric. The electric detonating as-                      free at both sides of the knot (fig. 87). When
          sembly is a length of detonating cord                      fabric is used to cover the detonating cord, the
           (approximately 2 feet) with an elec-                      fabric must not be removed. The knot should
          tric blasting cap attached (B, fig. 85).                   not be placed in water or in the ground unlesS
     (3) Attachment       0/ assembly to system.                     the charge is to be fired immediately.

76                                                                                                                   AGO 7258~


                                                                                    BLASTING  CAP
                                                                                    CRIMPED TO
        ELECTRIC                                                                    DETONATING  CORD

                                TO INITIATOR

                           Figure   84.   Detonating   cord priming   of pole charge.

                                                           cient length, will detonate an almost unlimited
is c. Branch L'
    fast         tne Connections.   A branch line          number of charges. The ring main makes the
  fig. 26) or to a . mam I'
         ened          . me by means of a clip             detonation of all charges more positive because
(                                                          the detonating wave approaches the branch
 (fig. 88)     a girth hitch with one extra turn
and th . The angle formed by the branch line               lines from both directions and the charges will
less th e cap end of the main line should not be           be detonated even when there is one break in
blast .an 90° from the direction from which the            the ring main. Branch lines coming from a
  Ine mIS coming' • at a sma II angle. the branch
  . .                         er                           ring main should be at a 90 angle. Kinks in
I                                                          lines should be avoided and curves and angles
 ing de~y be blown off the main line without be-
end of ~~ated. At least 6 inches of the running            should be gentle. Any number of branch lines
tie.        e branch line is left free beyond the           may be connected to the main line, but a
                                                            branch line is never connected at a point where
bring"Ring J1r! atn. A ring main is made by
   d.             •                                         the main line is spliced. In making detonating
      lllg the rme back in the form of a
                    .                                       cord branch line connections, avoid crossing
Ioop and                                                    lines. However, if this is necessary, be sure
and 0      attachmg It to itself with a girth hitch
      ne extra turn (fig. 89). This, if of suffi-                                                       77
AGO 7258A
that the detonating cords are at least a foot
                                                                            cut each other and possibly destroy. the firing
apart in places where they cross, or they wiII                              system.

                                                       NONELECTRIC           ~                  ATTACH WITH FRICTION           TAPE      TO
                                                       BLASTING CAP~~                           OR LENGTH  OF STRING                   CHA~
 00._--.,. 0 F====================~;;~J..~V~Ir:Li2iT7iIi'i".,7S.-f3
                              T.   IME   FUSE_                                             ./
                                                                                                  DE TONAT I NG CORD ~

                                                           'C-6       IN~                                                    S~~~~E

u~~--------------                                                                                                                             _
                                                                                                        ELECTRIC                        ..---'
                                                           ''---              .   ~/8LAsrINGCAP
                                                                                  ~                                      ~

                                                             ~                                           ~DETONATING              CORD

                          Figure     85.    Electric   and nonelectric      assemblies      attached    to main line.


                                              TO CHARGES


Figure   86.    Fastening   two lines 01 detonating         cord to
               a single blasting cap assembly.

71. Handling         Detonating            Cord Misfires
   a. Failure of Nonelectric Blasting Cap. If
a nonelectric blasting cap initiator attached to
detonating cord fails to function, delay the in-
vestigation for at least 30 minutes. Then cut
the detonating cord main line between the blast-
ing cap and the charge, and fasten a new blast-
ing cap initiator on the detonating cord.
                                                                                         Figure   87.    Square    knot connections.

                                                                                                                                       AGO 72r;8A
                                                               nating cord leading to a cnargt::           UCWU"""""         -.

                                                               the charge fails to explode, when above ground,
                                                               delay investigation until it is certain that the
                                                               charge is not burning; but when below ground,
                                                               wait 30 minutes. If the charge is intact, insert
                                                        ....   a new primer. If the charge is scattered by the
                                                               detonation of the original detonating cord, re-
                                                               assemble' as much of the original charge as
                                                               possible, place a new charge if necessary, and
                                                               reprime.    Make every attempt possible to re-
                                                               cover all explosives scattered by misfire, par-
                                                               ticularly those used in training exercises.

                                                                   CLOVE HITCH
                                                                   WITH TWO EXTRA
F'7Uure 88.
              Girth hitch Wt 'th one extra turn ccnnecttng
                 branch line to rnain line.

   b. Failure ~f El' ectnc Blast1,ng Cap. If an
exposed el
natin        ectnc blasting cap fastened to deto-
       g .                     .
hlachl' cord fa'l t fire, dIsconnect the blasting
blastl'                         .      .
        ne Immed' la t e I and Investigate.
            .             y                 Test the
If neeng Clrc U1 f or any breaks or short circuit.
   c. F~i~ary, replace the original blasting cap.
ing cord ~r~ of Detonating Cord. If detonat-
exposed ails ~o function at the explosion of an
Vestl'g t el.ectrlc or nonelectric blasting cap in-                                                        GIRTH HITCH
cap to a e 1mme d'
        th                                      '
                    lately. Attach a new blasting                                                          WITH ONE
it proper~ydetonating cord, taking care to fasten                                                          EXTRA TURN

   d         .
.      Failure . 0f . B ranch L1,ne. If the detonat-
lng .cord                       .
fails f maIn lIne detonates but a branch line
and fireasten a bl as t'Ing cap to the branch line
          1 separately                                              F1'gure 8.9,   Ring   main   with   branch   lineR,
   e. Fail ure of Charge to Explode. If the deto-

                                      Section    IV. DUAL FIRING SYSTEMS
                                                               a dual firing system should be used whenever
72. Redudlon         of Misfire    Risks                       time and materials are available. It may con-
  . a. The use of a d ua I firIng system greatly
  Increas                          .                           sist of two electric systems, two nonelectric
                          b'l't                " " .",-'
           ,es the pr 0b all y of successful-firIng,           systems', or one electric and one nonelectric
  I n Combat         .
                                                               system. The systems must be entirely inde-
  battl .' ' mIsfires may cause the loss of
  able es ' In tr alnlng, they cause the loss of valu-
        ti          . ,                                        pendent of each other and capable of firing the
  investi;:t:nd      endanger the lives of those that          same charge.
  Possibl        them. It is necessary to take every
  tio che precaution to avoid misfires of demoli-              73. Nonelectric      Dual Firing System
     n      arges,                                               This consists of two independent nonelectric
     b. The                    .
. qUently th f aI'1ure of firmg circuits is most fre-          systems for firing a single charge or set of
                e cause of demolition misfires. Thus
 ACO 7258A
                                                               TIME   FUSE

                               Figure   90.   Nonelectric   dual firing system.

charges. If two or more charges are to be fired
simultaneously, two detonating cord ring mains
are laid out, and a branch line from each
                                                            The . firing wires of the two circuits should be
                                                            kept separated so that both will not be cut bY
                                                            a single bullet or a single shell fragment.  The
charge is tied into each ring main. Figures 90
                                                            firing points also should be at two separate
and 91 show the layouts for nonelectric dual                locations.
firing systems.
                                                            75. Combination       Dual Firing System
74. Electric Dual Firing System
                                                               The combination dual firing system requires
   Thh~ dual firing system consists of two inde-
                                                            an electric and nonelectric firing circuit (fig. 1
pendent electric circuits, each with an electric
                                                            93) . Each charge has an electric and nonelec" ~
blasting cap in each charge, so that the firing
                                                            tric primer.  Both the electric and nonelectric
of either circuit will detonate all charges.
                                                            circuits must be entirely independent of each
Thus, each charge must have two electric prim-
                                                            other. The nonelectric system should be fired
ers. The correct layout is shown in figure 92.              first.                            .

                                                                                                       AGO 725M

                         Figure   91.   Dual detonating    cord priming,    using   two ring mains.



                                         Figure   92.   Electric   dual firing s1/stem.

AGO 7258A

    323-661 0 - 68 - 6

                                                  TIME   FUSE

                     Figure   93.   Combination   dual firing   8Y8tem.

                                                                          AGO   72fi8A
                                                                       CHAPTER 3

                                   CALCULATION                   AND         PLACEMENT OF CHARGES

                                                             Section     I. INTRODUCTION
                                                                                 a. Type of Explosive.             Explosives used in
76~ Cflllcal        Factors in Demolitions                                              military operations and their application to
                                                                                        demolition projects are shown in table VIII.
                            .         ..
tyPehe critical . fa Ct ors III d emohtlOns are the
      of ex
and t      .ploslve used and the size, placement,
      amplng of the charge.

                                                   Table VIII           Characteristics         of Explosives
                                                                                                              1       Relative
                                                                                                                                  IntenlltY ot       v.'atl-r
                                                                                         I       Approx.          effectivenesl
                                                                                                                                    poilonoul     rt'tIlstance
                                                                                               velocity of         Il8 external
                                                                       Smallest cap •          detonation                             tuml'l
                                                                        required for                                  charl(e
            Name                           Principal   use                                    ( meter/see)        (TNT-l.OO)
                                                                          detonation            (feet/Bec)
                                                                                                                                  Dangerous      Excellent
                                                                                              6,900 mps
TNT                                                                                          23,000 fps
                                                                                                                                  Dangerous      Excellent
                                                                                              7,000 mps               1.20
                                    Main charge, booster
Tetrytol                                                                                     23,000 fps
                                     charge, cutting                      Special
                                     and breaching                       blasting                                     1.34        Dangerous      Good
                                                                                              7,625 mps
Cornposition       C 3                charge, general                       cap
                                                                                             25,018 fps
                                      and military    use                                                                         Slight         Excellent
                                  _   in forward areas                                       8,040 mps                1.34
Composition        C 4                                                                       26,379 fps
                                                                                                                      0,42        Dangerous      Poor
                                                                                             3,400 mps
A;monium         Nitrate             Cratering     and ditch-                                11,000 fps
                                       ing                                                                                        Dangerous      Good
                                                                                             6,100 mps                0.92
Alilitary   D         .              Quarry      and   rock                                  20,000 fps
  All           ynamlte
                                       cuts                                                                            0.65
                                                                                             4,600    mps                                        Good      (if
                                     Land clearing,                                          15,000    Ips                        Dangerous      fired
Stra'   h                 400/0        cratering   quarry-                No.6                                        0.79
     19 t Dynamite                                                                           5,500    mps                                        within 24
                                       ing, and general                commercial
   (Commercial)    50 %                                                                      18,000    Ips                                       hours)
                                                                           cap                                         0.83
                                        use in rear areas                                    5,800    mps
                          600/0                                                              19,000    fps

                                                                                             2,700    mps              0.41
                           40%                                                                8,900   Ips                         Dangerous      Poor
Arnrnonia                                                                 No.6                                         0,46
                                     Land clearing,                                          3,400    mps
                                       cratering  quarry-              commercial
  Dynamite                50%                                                                11,000    ips
                                       ing, and general                    cap                                         0.53
  ( commercial)                                                                              3,700    mps
                                       use in rear areas                                     12,QOO    ips
                           60%                                                                                         0.42
                                                                                             2,400     mps
                           40%                                                                7,900    jfps                       Slight         Good
                                                                          No.6                                         0,47
                                     Land clearing,                                          2,700     mps
Gelat. In Dynamite                                                     commercial
                                       cratering  quarry-                                     8,900    :fps
                                                                           cap                                         0.76
  (commercial)     50 %                ing, and general                                      4,900     mps
                                       use in rear areas                                     16,000     ips
AGO' ~258A
                                     Table       VIII.     Characteristics      of Explosives-Continued
                                                                                           Approx.            Relative
                                                                 Smallest cap •          velocity of       effectiveness
            Name                     Principal    use             required for                                             Intensity of         Water
                                                                                          detonation       as external       poisonous        resistance
                                                                    detonation           (metEOr/see)          charge          fumes
                                                                                         (feet/see)         (TNT-l.OO)
Ammonia                4010     Land clearing,                     No.6                  4,900   mps
 Gelatin                          cratering quarry-              commercial             16,000    ips                      Slight           Excellent
 Dynamite                         ing, and general                  cap                 5,700    mps
  (commercial)          60'/0     use in rear areas                                     18,700    ips
                                Detonating        cord              Special                                                                                -
PETN                                                               blasting             7,300 mps                1.66      Slight           Good
                                Blasting     caps                     cap               24,000 ips
                                                                   Special              7,100 mps
TETRYL                          Booster charge                     blasting             23,300 ips               1.25      Dangerous        Excellent
RDX                             Base charge in blast-                                    8,350 mps               1.50
                                  ing caps                                              27,440 ips
                                                                   Special               7,800 mps                                                         -
Composition      B              Shaped charges                     blasting             25,600 ips               1.35      Dangerous        Excellent

                                                                    Special              4,900 mps                                                         -
Amatol     80/20                Bangalore     torpedo              blasting             16,000 ips               1.17      Dangerous        Poor
Black Powder                    Time blasting       fuze             N/A                  400 mps                0.55      Dangerous        Poor
                                                                                         1,312 ips
• EIl!ctric or nondLoctr.c                                     Abhrevlatlon.:     fps    -   feet per .~cond
                                                                                                                               No. -    number
                                                                                  mps -      meters per second
                                                                                                                               sec. -   second (s)
                                                                                  N/A -      not applicable

   b. Size 01 Charge. The amount of explosive                                     of the destructive effect is lost. To retain' as
used in a demolition project is determined by
                                                                                  much of this explosive force as possible, ma-,
formula calculation, and by means of a comput-                                    terial is packed around the charge. This ma-
ing tape or tables.     Formulas for computing                                    terial is called tamping material or tamping,
specific charges-timber        and steel cutting,                                 and the process, tamping.     On the other hand,
breaching, and so on-are       given in succeeding
                                                                                  an internal charge (one placed in the target to
sections of this chapter.    In the formulas (for
                                                                                  be destroyed) is confined by packing material in
example, P         =
                D~), the value of P is the amount
                                                                                  the borehole on top of the charge as is done in
of TNT (in pounds) required for external
                                                                                  quarrying and cratering.     This is called stem-
charges.    If other explosives are used, the
                                                                                  ming.Explosive      charges are generally tamped
value of P must be substituted according to the                                   and stemmed as described below.
strength of these other explosives in relation to                                    d. Charge Placement.
TNT. The substitution is computed by divid-
                                                                                        (1) Charges should be placed at the posi-
ing the P value (TNT) by the relative effective-
                                                                                            tion that will provide maximum effec-
ness factor for the explosive to be used. Steel
                                                                                            tiveness.   For cratering,     they are
and timber charges should be computed by
                                                                                            placed in holes in the ground; for
formula when possible.
                                                                                            breaking or collapsing stone or con-
   c. Tamping.    The detonation of an explosive
                                                                                            crete, they are properly located on the
produces pressure in all directions.        If the
                                                                                            surface or in boreholes; for cutting
charge is not completely sealed in or confined
                                                                                            standing timber they may be tied on
or of the material surrounding the explosive is
                                                                                            the outside or placed in boreholes,
not equally strong on all sides, the explosive
                                                                                            whichever is the more practical.
force breaks through the weakest spot and part
              ,                                                                         (2) Charges are fastened to the target by
84                                                                                                                                             AGO 7258A
                                                            surface. In drill holes, tamping should not be-
          wire, adhesive     compound, friction             gin until the explosive is covered by at least one
          tape, or string; propped against the              foot of stemming. Light materials are not ac-
          target by means of a wooden or metal              ceptable, as they are apt to blowout of the
          frame made of scrap or other avail-               borehole and cause incomplete destruction;
          able materials; or placed in boreholes.           neither are flammable materials like paper,
          Special accessories are issued for this           sawdust, and sacking, which may ignite.
          p~rpose-adhesive       compound,    the               b. External Charges.      These charges are
          rIvet-punching powder-actuated    driv-           placed on the surface of the target. They are
          er, the earth auger, and pneumatic                tamped by covering them with tightly packed
          tools (para 29-41).                               sand, clay, or other dense material.     Tamping
                                                            may be in sandbags or loose. For maximum
77. Types of Charges                                         effectiveness the thickness of the tamping
Ch:' Internal Charges. Internal charges are                  should at least equal the breaching radius.
Th rges placed in boreholes in the target.                   Small breaching charges on horizontal surfaces
cl ese are confined by tightly packing sand, wet             are sometimes tamped by packing several
op";'. or other material (stemming)        into the          inches of wet clay or mud around them. This
    ning. This is tamped and packed against                  process is called mudcapping.
th e expl OSIve to fill the hole all the way to the

                                 Section    II. TIMBER-CUTTING          CHARGES
78· S. and Placement of Charge
     Ize                                                         p==-
Siv~or;ntamped            external charges, block explo-         P    == pounds of TNT required,
C4) .( NT, tetrytol, and Composition C3 and                      p    == least diameter of the timber in inches
in lIS adequate, as it is easily tied or fastened                            or the least dimension of dressed
fo P ace and the charge size is calculated by                           timber, and
th r~ula based on its effectiveness in relation to            40 == constant
Foa of TNT (relative effectiveness factor).                 Adjustment for explosives other than TNT will
dy r tam pe d Internal.           charges in boreholes,     be made using the relative effectiveness factor
Conamit e IS generally used as it is the most               (table VIII) that pertains to the particular ex-
cart .dO? t             I                       .
                         ace because ' of the SIze of the   plosive being used. The amount of explosive
 confirl ge and IS powerful enough because it is            required to cut a round timber 30 inches in
 ali k"ned                        .
                It" IS ImpractIcal to attempt to cut        diameter using an untamped external charge
 lat dinds of timber with charges of a size calcu-           is determined as follows:
     e fro          .
 Var' t. m a SIng Ie formula. There is too much                         D2
 localit IOn' m d'ff ,erent kinds of timber from
                       I                                          p==-
 "'"     y to localIty.          Accordingly   test shots               40
 &llUst b
 cha       e made to determine' the ' size of . the               D   == 30 inches
 ula r~e to cut a specific type of timber. Form-
 'lid s or the calculation of these shots are pro-                p ==(30)2 ==22.5 pounds of TNT.
  tr ed for untamped external charges felling                            40
 chees f'or an abatIs, and for tamped 'internal                b. Formula lor PartiallY cutting Trees to
     arges. They are as follows:                             Create an Obstacle or Abatis. 'Vhen cutting
. arges '. For cu tt'mg trees, pIles, posts, beams,
or oth
          Formula     for    Untamped
                                                             trees and leaving them attached to the stumps
                                                             to create an obstacle, the formula     P ==50
te      er tImber members with an untamped ex-
th rnalcha rge, th e foliowmg formula IS used for
                           .             .                   isused to compute the amount of TNT required
In e test shot for either round or rectangular               for the test shot. The result of the test shot
   embers:                                                                                                    85

 A.GO 7258A
will determine the need for increasing or de-
creasing the amount of explosive required for
subsequent shots                                                     CHARGE
                                                                    (ELECTRIC              .
   c. Formula For Tamped Internal Charges.                           BLASTING
                                                                        CAP)               .~
Tamped internal cutting charges may be calcu-
lated by the following formula:
      P    =   pounds of explosive required,
      D    =   diameter     or least   dimension               of
                . dressed timber, in inches, and
     250   =   constant
   Note.  P      =any explosive;       relative    effectiveness
factor is not pertinent.
The amount of explosive required to Ctlt a 15-
inch diameter tree, using tamped internal
charges, is determined as follows:
               152    225
      P    = --= 250 = 0.90 or
           • 250
                 --                         1 pound

  Note.    See rounding     off rule para    81b(4).

   d. External    Charge Placement.      External
charges are placed a~ close as possible to the
surface of the timber regardless of the kind of
cut desired (fig. 94). Frequently it is desirable
to notch the tree to hold the explosive in place.
If the tree or timber is not round and the direc-
tion of fall is of no concern, the explosive is
placed on the widest face so that the cut will be
through the least thickness.    The tree will fall
toward the side where the explosive is placed,
unless influenced by lean or wind. To make the
direction of fall certain a "kicker charge," a
one-pound block of 'TNT, placed about two-
thirds of the distance up the tree on the oppo-
site side has proved excellent         (fig. 94).
Charges on rectangular or square dressed tim-
ber are placed as shown in figure 95.
                                                                          Figure   9-'.   External timber-cutting   charge.
   e. Internal   Charge     Placement.     These
charges are placed in boreholds parallel to the
greatest dimension of cross section and tightly                      holes are tamped           and the charges       are fired
tamped with moist clay or sand. If the charge                        simultaneously.
is too large to be placed in one borehole, bore                      79. Abatis
two side by side. On round timber, bore the
two holes at approximately right angles to each                         Charges for making fallen-tree obstacles are
                                                                     placed the same as those in paragraph 78, ex-
other, but not to intersect (fig. 96). Both bore-
                                                                     cept that they are placed approximately 5 feet
                                                                                                                       AGO 7258A
                                                             above ground level. To make the obstacles
                                                             more difficult to remove, they should be mined,
                                                             boobytrapped, and covered by fire. To be ef-
                                                             fective these obstacles should be at least 75
                                                             meters in depth and the felled trees should ex-
                                                             tend at a 45 angle toward the enemy.

                                                                   Figure   96.   Internal timber-cutting charg~.
Figur e   9 5.    External   cutting charge on rectangular

                                              STEEL-CUTTING CHARGES
                                        Section III.
                                                              is transmitted    directly to any sub-
                                                              stance in contact with the charge,
80. Cutfm~ Steel with Explosives
  a      .
                                                              other characteristics being equal.
    . ~nnctPles of Detonation.                            (2) A high explosive charge detonated in
      ( ) When.a high explosive detonates, the                direct contact with a steel plate pro-
           eX~lo~Ive changes violently from a                 duces easily detectable destructive
           s~hd Into compressed gas at extremely              effects. An indentation or depression
           hIgh pressure.    The rate of change is
                                                              with an area about the size of the
           determined among other things by the
                                                               contact area of the explosive charge
           type of explosive and the density, con-
                                                               is made in the surface of the plate
           finement, and the dimensions of the
                                                               where the charge is exploded. A slab
           charge. Thus the detonation releases
                                                               of metal-a     spall or scab--is torn
           tremendous pressure in the form of
           a shock wave which, although it exists              from the free surface of the plate di-
                                                               rectly opposite the explosive charge.
           f~r only a few micro-seconds at any
            gI~en point, may shatter and displace              This spalled metal is approximately
            ?bJect~ in its path as it proceeds from            the shape of the explosive charge, but
                 Its pOInt of origin.     This shock wave                                                           81

 AGO 7258A
        its area is usually greater than the                    onstrated conclusively that the opti.
        contact area of the charge. The steel                   mum ratio of charge width to charge
        is split or fractured under the explod.                 thickness is about 3:1 for contact steel
        ed charge along its entire length, and                  cutting charges placed on structural
        finally, a cross fracture is formed                     members 3 inches thick or less. They
        across the end of the charge away                       have also demonstrated that the point
        from the point of initiation.      Varia.               of charge initiation has no significant
        tions in the dimensions of the charge,                  effect on the shattering power of con-
        the shape of the steel member under
                                                                tact charges on steel. Successful ex.
        attack, and the placement of the
                                                                plosive cutting of steel bars and
        charge in relation to the steel mem.
                                                                structural    steel beams with certain
        ber can alter the destructive effects
                                                                contact charges, however, requires
                                                                charge initiation at specific points.
 b. Significance of Charge Dimensions.
                                                                These findings are applied in the dis.
    (l) The force of an explosion is propor-
                                                                cussion     on steel.cutting   formulas
        tional to the quantity and power of                     given below.
        the explosive, but the destructive ef-
                                                           (2) Thus, in the preparation of steel cut-
         fect depends on the contact between
                                                                ting charges, the factors of type, size,
        the explosive and the target and on
                                                                and placement of the explosive are
        the manner that the explosive is
                                                                important for successful operations.
        directed at the target.    For the maxi-
                                                                The confinement or tamping of the
        mum destructive effect against a steel
                                                                charge is rarely practical or possible.
         target, an explosive charge with a
                                                                Formulas for the computation of the
         configuration    and dimensions opti-
                                                                size of the charge vary with the types
         mum for the size and shape of the
                                                                of steel-structural,   high carbon, and
         target must be detonated in intimate
                                                                so forth. Placement, frequently hard-
         contact with the steel along the de-
                                                                er to accomplish. on steel structures
         sired line of cut. As any air or water
                                                                than on others, is aided by the use of
         gap between the charge and the steel
                                                                plastic explosive and the Ml18 special
         greatly reduces the cutting effect,                    sheet explosive.
        close contact is essential. An optimum
                                                        c. Explosive Used. Steel cutting charges
         relation must exist between the area
                                                     are selected because of their cutting effect and
         of the charge in contact with the tar.
                                                     adaptability    to placement.     Plastic explosive
         get and charge thickness in order to
                                                      (C4) and sheet explosive Ml18 are the most
        transmit the greatest shock. If any
                                                     desirable as they have high detonation velocity
         given weight of explosive, calculated
                                                     and other characteristics that give them great
         to cut a given target, is spread too
                                                     cutting power. C4 (M56Al) can be molded or
         thinly, there will be insufficient space
                                                     cut to fit tightly into the .grooves and angles of
         for the detonation to attain full ve-
                                                     the target, particularly structural steel, chains,
         locity before striking the target. The
                                                     and steel cables; but the Ml12 block, also C4,
         shock wave will tend to travel more
                                                     is more adaptable because of its adhesive com-
         nearly parallel than normal to the
                                                     pound on one face, which fixes it more securely
         surface over much of the area; and
                                                     on the target.      Sheet explosive, because of its
         the volume of the target will be ex-
                                                     width (3 in.), thickness (14 in.), and adhesive,
         cessive for the strength of the shock
                                                     is more desirable for some steel targets than
         wa ve. On the other extreme, a thick
                                                     either the M5Al or Ml12 demolition block.
         charge with narrow contact area will
                                                     TNT, on the other hand, is adequate, generally
         transmit the shock wave over too little
                                                    .available, and cast into blocks that may be
         of the target with excessive lateral
                                                     readily assembled and fixed, but not molded to
         loss of energy. Test results have dem.      the target.

                                                                                               AGO 7258A
                                                                    inches, of the steel member to be
81. Size of Charge Determined by Type                               cut, and
   . and Size of Steel
                                                              ~   == constant
  a. Types of Steel.                                          8
      (1) Structural.        Examples of this are 1-       (2) Formula for other steels.
           beams, wide-flanged beams, channels,               (a) The formula below is recommended
            angle sections, structural       tees, and            for the computation     of cutting
            steel plates used in building             or          charges for high-carbon or alloy
            bridge construction.        These are the             steel, such as that found in ma-
            types of steel usually present in demo-              chinery.
            lition projects.     The formula in b(l),            p == D2
            below, is applicable to structural steel,            P == pounds of TNT
            except for cutting slender structural                D == diameter or thickness in inches
            bars (2 inches or less in diameter)                        of section to be cut.
            where placement difficulties require             (b) For round steel bars, such as con-
            the use of the formula in b(2) (b) be-               crete reinforcing' rods, where the
            low.                                                 small size makes charge placement
       (2) High-carbon.         This type of steel is            difficult or impossible     and for
             used in the construction         of metal-          chains, cables, strong. forgings,
             working dies and rolls. The formula                 steel rods, machine parts, and high.
             in b (2) (a), below, is applicable.                 strength tools of a diameter of 2
       (3)Alloy.      Gears, shafts, tools, and plow-             inches or less use-
             shares generally are made of alloy                   p==D
             steel.    Chains and cables also are                 P == pounds of TNT
             often made from alloy steel; some,                   D == diameter in inches of section
             however, are made of a high-carbon                        to be cut.
             steel. The formula in b (2) (a), below,              Such steel, however, may be cut by
             applies to high carbon or alloy steel.                 "rule of thumb:"
        (4) Nickel-molybdenum          steel and cast                    For round bars up to 1 inch in
             iron.     Cast iron, being very brittle,                      diameter, use 1 pound TNT.
             breaks easily, but nickel-molybdenum                        For round bars over 1 inch up
              steel cannot be cut by demolition                            to 2 inches in diameter, use 2
              blocks. The jet from a shaped charge                         pounds of TNT.
              will penetrate it, but cutting will re-       (3) Railroad rail. The size of railroad
              quire multiple charges.       Accordingly,         rail is usually expressed in terms of
              nickel-molybdenum steel should be cut              weight per yard.        Rails over 80
              by some method other than explo-                   pounds per yard (more than 5 inches
              sives-acetylene      or electric cutting           in height) may be cut with 1 pound of
    b         tools, for example.     .                          TNT. For rails less than 80 pounds
      . Calculation of Charges.                                  per yard (5 inches or less in height),
        (1) Formula for structural steel. Charges                 Ih pound of TNT is adequate.
              to cut I-beams, builtup girders, steel         (4) "Rounding-o!f" rule. Charges calcu.
              plates, columns, and other structural              lated by formulas should be "rounded.
               steel sections are computed by formu-             off" to the next higher unit package
                                                                 of explosive. However, when a lh.
               la as follows:
                                                                 pound charge is required, and only
                     3                                            2~4-pound blocks are available, cut the
             P=-        A                                         blocks to proper size if feasible. For
                                                                  charges other than TNT, apply the
             P   =   pounds of TNT required,
             A   =   cross-section area, in      square                                               89

 AGO 7268A
         "rounding off" rule at completion of
         relative effectiveness factor calcula,;.
     (5) Problem: cutting steel I-beam.       De
         termine the amount of TNT required
         to cut the steel I-beam shown in figure                                  p=o
         97. The solution is given in the figure.                                 P = POUNDS OF TNT REQUIRED AND
     (6) Problem: explosives other than TNT.                                      D = DIAMETER IN INCHES OF STEEL                CHAIN TO BE CUT
                                                                                  0= lINCH
         Determine the amount of C4 explo-
                                                                                  P = I
         sive required to cut the steel I-beam in
                                                                                  P = I POUND OF TNT, IF BLOCK WILL BRIDGE LINK'
         figure 97.                                                                   IF NOT, USE TWO BLOCKS ONE ON EACH SIDE'
                                                                                      OF LINK                 '
             The amount of TNT       3 64            =
                  As C4 is 1.34 times as effective as
                  P (of C4)     =~            = 2.5       pounds

                                      CHARGE CALCULATION. TNT
              318 IN

                                    AREA Of FLANGE        • 2 X 1/2 X~. ~ SQ ..

                                    AREA Of WEB • 3/8        X II • 4 1/8 SQ IN

                                    TOTAL AREA       W. 9 1/8 SQ IN
                                    p. 3/8 A
                                    p. 3/8 X9 1/8 .3         27/64
                                    USE      3 1/2   LB   OF TNT

     112 IN                                                                       . Figure   98.           1
                                                                                                     Cal cua t'lOn   0/   ch arge to cut steel    chain.

              l---~IN                                                                     (8) Use of the table in making         calcul~
                                                                                                   tions. Table IX below, shows the cor-
                                                                                                   rect weight of TNT necessary to cut
Figure    97.     Calculation   0/ charge 0/ cut steel I beam.
                                                                                                   steel sections of various dimensions
                                                                                                                                       .               3
         (7) Problem: cutting steel chain. How                                                     calculated    from the formula                P= -
             much TNT is needed to cut the steel                                                                                                       8
             chain in figure 98? The solution is                                                     A. In using this table:
             given in figure 98. Notice that the                                             (a) Measure separately the rectangular
             link is to be cut in two places (one cut                                             sections of members.
             on each side) to cause complete fail-                                           (1) Find the corresponding      charge for
             ure. If the explosive is long enough                                                 each section by using the table.
             to bridge both sides of the link, or                                            (c) ,Total the charges for the sections.
             large enough to fit snugly between the                                          (d) Use the next larger given dimen-
             two sides, use only one charge; but if                                               sion if dimensions of sections do
             it is not, use two separately-primed                                                 not appear in the table.
                                                                                                       Caution:  Never use less than             the cal-
                ,                                                                                    culated amount.

90                                                                                                                                           AGO    7258A
                                                       Table     IX.         TNT       Needed        to Cut Steel              Sections

                                                       pounds    of explosive      0   for rectanln1lar        steel s~tion.        of Itiven dimenllions
tAyerage       I
                                                                                       Heistht of section in inches
                                                                                                                               12        14       16        18    20   r    22    U
8e('tion in                                                                                      I                 11
                                                                                                        10 .
                                                                                                                                                                 1.9       2.1   2.3
                                                            6           7          8
                                                                                                                                        1.3     1.5     1.7
                    2       3          4           5
                                                                                                       1.0       1.1      1.2                                    2.8       3.1   3.4
                                                                               0.8        0.9                                           2.0     2.3     2.6
%                                  0.4           0.5       0.6         0.7                                       1.6      1.7                                    3.8       4.2   4.5
                   0.2     0.3                                                 1.2        1.3          1.4                                      3.0     3.4
                                                           0.9         1.1                                                2.3           2.7                                5.2   5.7
%                  0.3     0.5     0.6           0.7                                      1.7          1.9       2.1
                                                                                                                                                3.8     4.3      4.7
                                                           1.2         1.4     1.5                                        2.9           3.3                                      6.8
%                  0.4     0.6     0.8           1.0                                      2.2          2.4       2.7
                                                                                                                                                4.5     5.1      5.7       6.3
                                                                       1.7     1.9                                        3.4           4.0                                      7.9
%                  0.5     0.7     1.0           1.2       1.4
                                                                                          2.6          2.8       3.1
                                                                                                                                                5.3     6.0      6.6       7.3
                                                                       2.0     2.3                                        4.0           4.6                                      9.0
~                  0.6     0.9     1.2           1.4       1.7
                                                                                          3.0          3.3       3.7
                                                                                                                                                6.0     6.8      7.5       8.3
                                                           2.0         2.4     2.7                                        4.5           5.3
%                  0.7     1.0     1.4           1.7                                      3.4          3.8       4.2
1                                                          2.3         2.7     3.0
                   0.8     1.2     1.5           1.9
                          1. Measure       rectanl/:ular   sections of memhers           separately.
     To use:
                          2. Usinl/: table, find charl/:e for each section.
                          3. Add charges for sections to find total charge.
                          4. If dimensions of sections do not appear on table. use the next larger dimension.

            e. Problem. The problem in figure 97 may be solved as follows:
                        Charge for flanges:                                                                                    Charge for web:
                           width       =
                                    5 inches                                                                                     height         =
                                                                                                                                           11 inches
                        thickness = 1/2 inch                                                                                     thickness =' % inch
                        Charge from table =                                                                                    Charge from table ='
                           1.0 pounds                                                                                            1.6 pounds
                                       Total charge:               2 flanges             == 2 x 1.0 == 2.0 pounds
                                                                         web             == 1 x 1.6 == 1.6 pounds
                                   Use 4 pounds of TNT.                                                              3.6 pounds
                                                                                                          c. Steel].f embers and Railroad Rails. Charge
                                                                                                       placement for cutting these is found in figures
 82. Charge               Placement
 at a. Steel Sections.      The size and type of a                                                     99 and 140.
 ell: I
 Q   eel ~ecfIon determine the placement of the                                                           d. Built-uP ].f embers.   Built-up members
 b P OSIvecharge. Some elongated sections may                                                          frequently. have an irregular shape. which
     e cut by placing the explosive on one side of                                                     makes it difficult to obtain a close contact be.
 th Ion completely along the proposed line
 of                                                                                                    tween the explosive charge and all of the sur-
 ind~u~ture. In some steel trusses in which the                                                        face. If it is impractical to distribute the
 tn IVldual members are fabricated from two or                                                         charge properly to obtain close contact. the
 b ore prim ary see t.Ions, such as angle Irons or
                                              .                                                        amount of explosive should be increased.
  \l~rs separated by spacer washers or gusset
    • ates, the charge has to be cut with the oppos:'                                                       e. Irregular Steel Shapes. Composition C4
  1ngp or t'
  d          IOns of the charge slightly offset to pro-                                                  (M2Al block) is a good explosive for cutting
  II b a sh.earmg actIOn (para 83d(4). HeaVier
     uce                  .                          .                                                   irregular steel shapeS because it is easily mold.
  al' eams, wide flange beams, and columns may                                                         . ed or pressed into plac~ to give maximum con-
  o .require auxiliary charges placed on the                                                             tact. A light coating of adhesive compound
                                                                                                         applied to the steel surface will help hold the
  i~ side of the flanges. Care must be taken to
   O\ls:r~ that opposing charges are never directly                                                      explosive on the target. The M112 block. also
   ne~t Sit? each other, otherwise they tend to                                                          C4 has an adhesive coating on one side and the
       b rahze the explosive effect.                                                                    Mi    18 sheet explosive has a similar coating,
   si . Rods, Chains, and Cables. Block explo-                                                            which makes placement easier (para 80c).
      ve, often difficult to emplace, is not recom-
                                                                                                               f. Securing Erpwsives in Place.                                   All ex-
   ;~~de~ for cutting steel rods, chains, and
     a es If plastic explosive is available.                                                                                                                                           91

     A.GO 72G8A
                                                      CHARGE    SPLIT AND
                                                      PLACED    ON TWO SIDES

     I - BEAM

                                                                        PLASTIC   EXPLOSIVE
                                                                        MOLDED    ON I-BEAM

                               Figure   99.   Placement   01 charges   on steel members.

plosives except moldable or adhesive types must
                                                                         (a) Thickness        of charge = 1/3 of the
be tied, taped, or wedged in place unless they
                                                                                thickness of M5Al block of plastic
rest on horizontal surfaces and are not in
                                                                                explosive (2/3 inch) for targets up
danger of being jarred out of place.
                                                                                to 19 inches in circumference          (6
   g. Precautions. In cutting steel, the charge
                                                                                inches in diameter);        and 1/2 the.
should be placed on the same side as the firing
                                                                                thickness of M5A1 block of plastic
party, as explosive charges throw steel frag-
                                                                                explosive (1 inch) for targets from
ments (missiles) long distance at high veloci-
ties.                                                                           19 to 25 inches in circumference
                                                                                 (over 6 to 8 inches in diameter).
83. Special Steel Cutting Techniques                                      (b) Base of charge     =    1/2 circumference
  a. Use of Special Techniques. Three types                                     of target.
of steel cutting charges are available for use,                           ( c) Long axis of charge       =    circumfer-
the saddle charge, diamond charge, and ribbon                                   ence of target.
charge.     They are prepared in advance for                           (2) Example. Determine the dimensions
transportation   to the site by wrapping them in                             of a charge for cutting a shaft 18
aluminum foil or heavy paper. Not more than                                  inches in circumference           (may be
one thickness of the wrapper should be between                               measured by a length of string) ..
the explosive and the target.                                             (a) Thickness    =    1/3 thickness of M5Al
   b. Saddle Charge. This charge is used on                                     block of plastic explosive          (2/3
solid cylindrical mild steel targets up to 8                                    inch).
inches in diameter.     Detonation is initiated at                       (b) Base    =            =
                                                                                           lh x 18 9 inches
the apex of the long axis (fig. 100).                                     (c) Long axis    =    18 inches.
       (1)   Size of charge.                                             Charge is 9 inches at base, 18 inches at
                                                                                long axis, and 2/3 inch thick.
                                                                                                               AGO 721i8A
                                                          THICKNESS     (2) Example.       Determine the size of a
                  TARGETS                                                     charge for cutting a steel alloy shaft
                  (I) UP TO 6 IN DIA (191N CIR) -1/3
                  THICKNESS OF M5AI (C4) BLOCK (2/3 IN)                       15 inches in circumference.
                  (2) OVER 6 IN TO 8 IN DIA (19 IN TO
                                                                           (a) Long axis == 15 inches.
                                                                           (b) Short axis == th x 15 == 7th inches.
                  25 IN CIR)= V2 THICKNESS OF M5A1
                  (C4) BLOCK (I IN)

                                                                           (c) Thickness == 1/3 the thickness of
                                                                                M5A1 block of plastic explosive or
                                                                                 2/3 inch. Charge is 15 inches at
                                                                                 long axis, 71/2 at short axis, and 2/3
                                                                                     inch thick.
                                                    END VIEW

                               SIDE VIEW
                                                                                     ~~%7      TOP VIEW

       L ~                                        J J
                                                     __ -"          [                        V_or                           .
                                                                                                               .-:l"",7:..._ _.

                                                                                               SlOE VIEW       .

                                                                                 EXPLOSIVE                   THICKNESS-    1/3     THICKNESS   OF
                                                                                       ,                     MMI    (C4) BLOCK(213 IN)
                               TOP VIEW

               Figure   100.   Saddle   charge.                                                END VIEW

                  Note. Steel alloy and mild steel targets
               over 25 inches in circumference (over 8
                                                                                                                                  POINTS OF
               inches in diameter) require the diamond                                                                            DETONATION
               charge   (c below).
                                                               SI«>RT AXIS   t
      (3) Placement.     The long axis of the                           L
          saddle should be parallel with the long
          axis of the target.  Detonation of the                                      Figure     101.     Diamond     charge.
          charge is by the placement of a mili-
          tary electric or nonelectric blasting                           (3) Placement.         \Vrap the explosive com-
          cap at the apex of the long axis.                                        pletely around the target so that the
                                                                                   ends of the long axis touch. Detonate
ca \, Diamond Charge.        This is used on high                                  the charges simultaneously from both
is r on steel or steel alloy targets (fig. 101). It
                                                                                   short axis endS. This may be done
   shaped like a diamond.                                                          by priming with two pieces of deto-
      (1) Size of charge. The size of the charge                                   nating cord of the same length with
            depends on the dimensions of the tar-                                   nonelectric blasting caps crimped to
            get.                                                                    the ends, or two electric blasting caps
         (a) Long axis of charge == circumfer-                              connected in series.
               ence of the target.                                      d. Ribbon Charge. This charge, if properly
         ( b) Short axis of charge == th the cir-                 calculated and placed, cuts steel with consider-
               cumference of the target.                          ably less explosive than standard charges. It is
         (c)    Thickness    of charge == 1/3 the                 effective on noncircular steel targets up to 2
                thickness of M5A1 block of plastic                 inches thick (fig. 102).
                explosive (2/3 inch).                                                                                                          93

AGO   7258A
                                                                                    steel member will be ruptured at ap-
CHARGE =              THICKNESS          OF CHARGE   =   3/4       .
3 TIMES                                                                             proximately the linear axis of the rilr
                      THICKNESS OF. TA7
THICKNESS                                                                           bon.
OF CHARGE                                                                       (4) Use on structural steel sections. The
                                                                                    ribbon charge (computed by formula
                                                                                    given in (2), above) has a proven ap-
                                                                                    plication to cutting structural    steel
                                                                                    sections (fig. 103). On wide-flanged
                                                                                    beams of less than 2 inches of steel
                                                                                    thickness, a C-shaped charge is placed
                           "-   LENGTH        OF CHARGE        =
              ~                 LENGTH,      ,OF TARGET
                                                                                    on one side to cut the web and half
                      ~~                                                            of the top and bottom flanges.      The
                                                                                    other sides of these flanges are cut by
            PRIMED         AT ONE   END ONLY
                                                                                    two offset ribbon charges, placed so
                                                                                    that one edge is opposite the center of
                                                                                    the C-shaped charge as shown in A,
                                                                                    figure 103. For beams with steel

             Figure    102.     Ribbon    charge.
     (1) Calculation.     The effectiveness of the
          blast depends on the width and thick-
          ness of the explosive.
       (a) Thickness of charge               =
                                       8A, thickness
             of the target.                                                                    A. BEAMS    LESS   THAN   2 IN      TH ICK .

       (b) \Vidth of charge              =
                                    3 x the thick-
             ness of the charge.
       (c) Length of' charge = length of the
                                                                                                                       OFFSET   FLANGE  CHARGE
              Note. Charge        should never be less than                                                            SO THAT ONE EDGE IS
            lh-inch thick.                                                                                             OPPOSITE
                                                                                                                                  AN EDGE OFTHE
                                                                                                                                  CHARGE TO
     (2) Example.          Determine the thickness                                                                     CUT OTHER SIDE OF
                                                                                                                     . FLANGE

           and width of a ribbon charge for cut-
           ting a steel plate 1 inch thick.
        (a) Thickness = %, thickness of target
                                                                                                B. BEAMS   2. IN THICK   OR    MORE
                    1 x%,=    8/il inch.
        (b) \Vidth = 3 x thickness of the charge
                3 x a/il 2tA, inches. Charge is
                                                                                                                          DETONATE     FROM
              o/t. inches thick and 2tA, inches wide.                  DETONATE
                                                                                   FROM                                   OUTER    EDGE

     (3) Detonation.         The ribbon charge is
           detonated from one end only. It may
           be necessary where the calculated                                                                             DETONATING      CORD
                                                                                                                         PRIMERS      MUST   BE
           thickness is small to "build up" the                                                                          OF   EQUAL     LENGTH

           detonating end with extra explosive.
           Either the electric or nonelectric cap is
           satisfactory.     The charge should ex-
           tend slightly over the target at each                                                           C. PRIMING
           end, to insure a complete cut. The                          Figure     103.    Placement of ribbon charges         on structural
                                                                                                  steel sections.
                                                                                                                                   AGO 7258A
                                                                    tric or nonelectric system.
               thickness of 2 inches and over, the off-                 Note. It is possible that on heavily-
               set charges are placed opposite an                   loaded beams the C-shaped ribbon ch~rge
               edge of the C-shaped charge as shown                 placed on one side (fig. 103) will be ade-
               in B, figure 103. For optimum re-                    quate. The uncut sides of the flanges may
               sults, the charges must be primed with               fail without the use of offset charges be-
                                                                    cause of the weight. This technique, how-
               three equal lengths of detonating cord
               :v ith blasting caps attached and placed
                                                                    ever,' must be used with discretion
                                                                    eliminate possibility of failure.

                In the charges as in C, figure 103 to
               provide simultaneous detonation. The
               three charges are initiated by an elec-

                                      Section   IV. PRESSURE CHARGES
                                                            d. Use of Table in ltfaking Calculations.
84• S' of Charge                                          Table X, gives the various weights of TNT re-
                                                          quired to provide suitable tamped pressure
d The, ~ressure charge is used primarilY for the          charges. The weights of TNT, in the table were
l' b
 ernohtlOn 0 f SImple span reinforced concrete
                                                          calculated from the formula P == 31P~ and the
 earn bridges and cantilever bridges.                 values were rounded off to the next highest
Tha. Formula      for Tamped Pressure Charges.            pound. To use the table proceed as follows:
     e amount of TNT required for a tamped                         Select the appropriate value in the
 pr essure ch arge IS calculated by the formula
 bel                 .                                        (1)
                                                                   "Height of beam" column.
'cal~~' If explosive other than TNT is used. the                   Read the weight of the TNT from the
      u ated value must be adjusted.                           (2)
                                                                   column corresponding to the thickness
       p   = 3H2T                                                   of the beam.
       P   = pounds    of TNT required for each              e. Example. The height of the beam in the
           beam (stringer).                               problem in figure 104 is 34 inches and the
      H    =height of beam (including thickness           thickness is 17 inches. In table X (36-inch
           of roadway) in feet                            height and 1S-inch thickness columns), the
II T       =thickness of beam in feet                     weight of TNT for the tamped pressure charge
   owever, the values of Hand T if not whole              is indicated as 41 pounds.     For untamped
n urnbe rs s h ould have the fraction expressed
i                                   '                     charges the weight values given in the table
  n l,4-foot increments by rounding off to the            are increased by one-third.
n ext
nev hi g h er 1/ it-foot d,menSIOn. Hand
                           .    .         Tare            8S. Charge Placement and Tamping
    er considered less than 1 foot.
                                                             a. Placement.   The correct amount of ex-
rt'lhb. Formula for Untamped Pressure Charges.            plosive is placed on the roadway over the cen-
 J.  e .v a I ca I
             ue                     .
                  culated for P by the above form-        terline of each stringer (fig. 104) and alined
ul a IS Increased by one-third if the pressure
            •                                             midwaY between the ends of the span. If a
ch arge IS not tamped to a minimum of 10
in h          .                                           curb or side rail prevents placing the charge
    c es.                                                 directly above the outside stringer, it is placed
                                                          against the curb or side rail. This does not
th c. Problem: Pressure Charges.     Determine            require an increase in the size of the explosive
b : amount of TNT required to destroy the
 t~'~e span sho~n in figure 104. The solution             charge.
 th IS problem IS found in the figure. Notice                b. Tamping.   Pressure charges should be
 f at the quantity of explosive given by the              tamped whenever possible. Effective tamping
 1'0:mula refers to the charge for each beam.             requires a minimum of 10 inches of material.
"pl us four of these 41-pound charges should be           All charges are primed to fire simultaneously.
   aced as shown in the figure.                                                                             9S

 AGO   7258A
                                                                            TAMPING   (MIN)


p. 3 H2 T
      T. 1.5                                       ~           /       .•
      P - 3)( 3 )( I. 5 • 40. 5                        ~./
USE    41 POUNDS      OF TNT      FOR EACH   CHARGE          T.17IN~
                                               SECTiON             V.      BREACHING           CHARGES
86. Criti~al Factors and Computation                                               similar material is calculated by the formula
d Breachmg charges are applied chiefly to the                                      below. By proper adjustment of the P-value,
 ~struction of concrete slab bridges, bridge                                       the charge size for any other explosive may be
Pflers, bridge abutments. and permanent field                                      readily determined.
. ort'fi catIons.
      I      .      The size ' placement and tamp-                                      P     R.JKC
Ing                         "
cr't.or confinement of the breaching charge are                                                =
                                                                                        P == pounds of TNT required
th I lcal factors - th'e sIze an d con finemen t 0 f
               .                                                                         R     =
                                                                                              breaching radius, in feet (b below)
bee explosIve being relatively more important                                            K = material factor, given in table XI
to cause of strength an d b u lk 0 f th e ma t'erIa Is                                           which reflects the strength and'
eh e breached.          High explosive breaching                                                 hardness of the material to be de-
ro a;;ges, detonated' in or against concrete and                                                 molished (c below)
b c , must produce a shock so intense that it                                            C == a tamping factor, given in figure 105
 . reaks or shatters the material.      The metal re-                                            which depends on the location and
lnforc' mg b ars often found in concrete are not                                                 tamping of the charge (d below)
   aways cut by breaching charges. ~ If it is
n ~e .ssary to remove the reinforcement, . the steel                                  Note. For brearhing walls 1 foot thirk or Ie,., in.
    ttIng formula (para (b) 81 b (2) (b» is used.                                   crease the total calculated ch arge by 50 perren t. Add
     a.. Calculation Formula. The size of a charge                                  10 percent     for charges      under       50 pounds.   .
 requIred to breach concrete, masonry, rock, or                                        b. Breaching Radius R. The breaching radius
                                  T bl Xl            V 1         f K (M aterta 1 F ac t or ) f or B r e ac hing Charges
                                                                             .                                                                    K
                                   a e                a ue   0                                                   Brt"Rc-hinll   rAIll1I1I
                                               Material                                                  All values
O~~ry         earth                                                                                                                              0.23
                                                                                                         All values
Poor ma sonry, s h ale and hardpan;              good timber            and earth constructIOn
                                                                                             .                                                   0.35
                                                                                                         Less than 3 feet
                                                                                                         3 feet to less than 5 feet
                                                                                                         5 feet to less than 7 feet
Good masonry,         ordinary    concrete,     rock                                                     7 feet or more
                                                                                                         Less than 3 feet
                                                                                                         3 feet to less than 5 feet
                                                                                                         5 feet to less than 7 feet
                                                                                                         7 feet or more
 Dense co ncre t e, first-class      masonry

 -                                                                                                       Less than 3 feet
                                                                                                         3 feet to less than 5 feet
                                                                                                         5 feet to less than 7 feet
  einforced     concrete      (concrete    only; will not cut steel reinforcing)                         7 feet or more

.--      --
   WALL OR                                UNTAMPED
                                                                         TAMPED OR
  ABUTMENT                                                                            FILL
                  T MPING

                                  Figure      105.     Value of C (tamping           factor)   for breaching      rharg ...

 AGO 7258A                                                                                                                                            97

        323-:;61 0 - 68 - 7
R is the distance in feet from 'an explosive in                   the thickness of the mass to be breached.    The
which all material is displaced or destroyed.                     breaching radius for internal charges is one-
The breaching radius for external charges is                      half the thickness of the mass to be breached if

                                      METHODS              OF     PLACEMENT
THICKNESS                                            TNT (lB)
     OF                                                                                             ANY   DISTANCE

                                                                            g: I'\~
CONCRETE                                                                                                   BETWEEN

                                 Latt' I
  IN FEET                                                                                                 CHARGES
                                                                                                           IN FEET
                                                                            O.~.                          INTER-   EXTER-
                    ~~                                                      J~
                                                                    T'      .:9    ~
                                                                                                           NAl      NAL
  COLUMN                   1          2                3             4
                                                                                        5   I   6    7      8       .9
      2                    16        28                15             8            ~                 1     2          4
      2   Y2               31        55                28            16            ~1                2     2~         5
      3                    41        67                38            21
                                                                                   ~                 4     3          6
      3~                   59        107               55            33
                                                                                   ~                 6     3~         7
      4                    88        159               81            49            ~                 8     4         8
      4~                   126       226               116           63
                                                                                   ~                 11    4Y2       9
      5                  157         282              144            79            ~7               16     5        10
      5~                 208         375              192           104
                                                                                   ~                20     5~       11
      6                  270         486              249           135
                                                                                   ~                21     6        12
      6 Y2               344         618              316           172
                                                                                   ~                26     6~       13
      7                  369         664              340           185            1~               33     7        14
      7~                 454         817              418           227
                                                                                   ~                40     7~       15
      8                  551     I   991              507           276
                                                                                   ~                49     8        16


     1.        10% has been added to the table for charges less than 50 lbs.
     2.        For best results place charge in shape of a square.
     3.        For thickness of concrete of 4 ft or less use charge
               thickness of 2 in (one block thick); over 4 ft thick use charge
               thickness of 4 in (one haversack of tetrytol or plas~ic (MSAl».
     To use table:

     1.        Measure thickness of concrete.
     2.        Decide how you will place the charge against the concrete.
               Compare your method of placement with the diagrams at the top
               of the page. If there is any question as to which column to use,
               always use the column that will give you the greater amount .
               of   TNT.
     3.        For calculating explosives other than TNT, use relative
               effectiveness factor (Table VIII).

                                     Figure   106.    Breaching    charge   calculations.

                                                                                                                   AGO    7258A
                                                         87. Placement and Number of Charges
  the charge is placed :nidway into the mass. If             a. positions.   In the demolition of piers, and
  holes are drilled less than halfway into the            walls the positions for the placement of ex-
  lllass, the breaching radi us becomes the longer
                                                          plosi~e charges are rather limited. Unless a
   distance from end of the hole to the outside of        demolition chamber is available, the charge (or
   the mass. For example, if a 4-foot wall is to be
                                                          charges) may be placed against one face of the
   ?reached by an internal charge placed 1 foot
                                                          target either at ground level, somewhat above
   Into the mass, the breaching radius is 3 feet.
   If it is to be breached by a centered internal
                                                          ground level, or beneath the surface.  A.  charge
                                                          placed above ground level is more effective than
   charge, the breaching radius is 2 feet. The
                                                        , one placed directly on the ground. '\~en sev-
   breaching radius is 4 feet if an external charge
                                                          eral charges are required to destroy a pIer, slab,
   is used. Values of R are rounded off to the next       or wall and elevated charges are desired, they
   highest 1/2-f06t.                                      are distributed equally at no less than 1 breach-
      c. Material Factor K. K is the factor that re-
                                                          ing radius high from the base of the object ~o
   flects the strength and hardness of the material
                                                        , be demolished. In this manner, the best use IS
   to be breached.     Table XI gives values for the
                                                          obtained from the shock ,waves of the blast.
  ,:actor K for various types of material. ,\Vhen it
                                                           All charges are thoroughly tamped with damp
   IS not known whether or not concrete is rein-
                                                          soil or filled sandbags if time permit~. (T~mp-
   forced, it is assumed to be reinforced.
                                                           ing must equal the breaching radius.) ~or pIers,
       d. Tamping Factor C. The value of tamping
                                                          slabs or walls partially submerged In water,
    ~actor C depends on the location and the tamp-
                                                           char~es are placed below the. waterline. . If
   Ing of the charge. Figure 105 shows typical
                                                           underwater demolition is essential, the
   lllethods for placing charges and gives values of
                                                          factor for the placement of tamp~d charges WIth
    C to be used in the breaching formula with
    both tamped and untamped charges.         In se-     earth is used.
    lecting a value of C from figure 105, a charge          b. Number of Charges.      The. number of
    tamped with a solid material such as sand or         charges required for demolishing a pier, slab,
    earth is not considered fully tamped unless it is    or wall is determined by the formula:
. covered to a depth equal to the breaching
    radius.                                                   N ==   fR                     .
       e. Use of Figure in Making Calculations. Fig-          N ==  number of charges        .    .
    Ure 106 gives the weight of TNT required to               W ==  width of pier, slab, or wall, In feet
    breach reinforced and dense concrete targets.             R ==  breaching radius in feet (par~ 86b)
    The weights of TNT in the table were calculated      If the calculated value of N has a fractlo~ less
    from the formula P    =   R3 KC and the values       than lh, the fraction is disregarded, but If the
    Were rounded off to the next highest pound.          calculated value of N has a fraction of Ih or
       f. Example. Using figure 106, calculate the       more, the value is "rounded off" ~o the ne~t
    amount of TNT required to breach a reinforced        higher whole number.       An exceptIOn to thIS
    concrete wall 7 feet in thickness with an un-        general rule is in calculated N-value be~wc~n
    tamped charge placed at a distance R above           1 and 2, in which a fraction less than Ill. IS dI~-
    the ground. From the figure (7 foot thickness        regarded    but a fraction of Ill. or more IS
    and untamped charges placed at a distance R          rounded ~ff to the next higher whole number,
    above the ground columns) the required weight        or   2.
    of TNT is 340 pounds.
                                        CRATERING       AND    DITCHING   CHARGES
                          Section VI.
                                                          tr~te charge is not available, other explosives
   88. Critical Factors                                   may be substituted.
    a. Explosive.   A special cratering charge,             b. Size and Placement of Charge.
  ammonium nitrate , issued in a waterproof metal   .          (1) Basic factors. In deliberate crntering,
  Container, is used. When the ammonium n1-                                                              99

   AGO 7258A
            holes are bored to specific depths and
                                                                                               be breached by charges placed in bore~
            spaced according to computation by.
                                                                                               holes drilled or blasted through it. (A'
            formula.     Deliberate craters are a
                                                                                               shaped charge readily blasts a smaIl~
            minimum of 8 feet deep. In hasty
                                                                                               diameter borehole through the pave~
          , cratering, holes are more shallow, con-
                                                                                               ment and into the subgrade). Concrete
            tain less explosive, and are spaced on
                                                                                               should not be breached at an expansion
            5-foot centers. ,The crater depth is
                                                                                               joint, because the concrete will shatter
            11;2 times the depth of the borehole.
                                                                                               irregularly.    After breaching, holes
            In ditching, test shots are made and
                                                                                               may be made by use of the earth rod
            the diameter and depth are increased                                               kit (para 41c) and widened by the
            as required. The size of the cratering
                                                                                               detonating cord wick (para 98b). Also
            charge is determined as described in
                                                                                               an M2A3 shaped charge (fig. 8) deto~
            paragraphs 89 and 90.
                                                                                               nated 30 inches above any kind of soil
       (2) Breaching hard-surfaced       pavements                                             will produce a borehole deep enough
            for cratering charges. Hard-surfaced                                               to accept a cratering charge (table
            pavement of roads and airfields is                                                 XII).    But since these shaped-charge
            breached so that holes may be dug for                                              boreholes are usually tapered in diam~
            cratering charges.     This is done ef-                                            eter, they should be enlarged by means
            fectively by exploding tamped charges                                              of a posthole digger, detonating cord
            on the pavement surface.     A I-pound                                             wick, or other device.
            charge of explosive is used for each 2
                                                                                       c. Confinement of Charge. Charges at crater~
            inches of pavement thickness.      It is                                 ing sites and antitank ditching sites are placed
            tamped with material twice as thick as
                                                                                     in boreholes and properly stemmed. Those at
            the pavement. The pavement may also
                                                                                     culvert sites 'are tamped with sandbags.

                                         Table XII.     Size 01 Boreholes           Made by Shaped        Charges

                                                                                                            M3 shanerl     charll,'e   M2A3 shaperl    char~e
   1                        Maximum         wall thickness      that can be perforated           _____
-2                          Depth of penetration             in thick walls ________________
                                                                                                           60 in                           36 in

-3      Reinforced                               Entrance
                                                                                                           60 in                           30 in

-4        concrete                                               --------------------------                5 in                            3% in                    ~
                            Diameter of
                              hole (in)
                                                                ---------------------------                   -
                                                                                                            3% in                          2%. in
                                                Minimum                                                                                                             I:

-6                                                               --------------------------                2 in                            2 in
                            Depth of hole with second charge                 placed over first hole
                                                                                                           84 in                           45 in
   7    Armor               Perfora tion      ______________________________________                                                   ,

-8         plate            A verage      diameter    of hole ____________________ -' ____
                                                                                                           A t least     20 in             12 in
                                                                                                           2% in                           1% in
   9                        Depth of hole with 50-in standoff                  __________________
-10                         Depth with 30-in standoff              _________________________
                                                                                                           72 in                           N/A
-11                         Depth with 42-in standoff              ___________________ ....
                                                                                                           N/A                             72 in

- 12    Permafrost                                                                                         N/A                             60 in
                            Diameter       of hole with average           (30-in)     standoff   ______
-13                                                                                                        N/A                             6 in to 1% in
                            Diameter       of hole with 50-in standoff              ________________                                                            -
- 14                        Diameter       of hole with normal           standoff     ______________
                                                                                                           8 in to 5 in                    N/A
                                                                                                           .26-30      in to 7 in          26-30 in to 4 in
  15                        Depth with average           (42-in)     standoff        _______________
                                                                                                           12 ft.
- 16    Ice
                            Diameter       with average        (42-in)     standoff     ____________
                                                                                                                                           7 ft
                                                                                                           6 in                            3% in
 • Boreho)l"   malle by Ihaped charI("    are cone-Ihaped.
                      ,                                        The diameters    Ihown   In thil table are top and bottom     measurements.

                                                                                                                                                    AGO 1258A        1
                                                             holes are 7 feet deep and the others are alter-
89. Deliberate Road Crater                                   nately 5 feet and 7 feet deep. The formula for
    A deliberate road crater may be made in all              the computation of the number of holes is:
rnater' Ia I except loose sand regardless of the                  N=~+l
t Ype 0 f road surface. The method shown in fig-
U                             '                                   L   = length.
                                                                               of crater in feet measured
  f.e .107 produces a clean V-shaped crater a                            acrosS roadway
rntIlllmum of 8 feet deep and 25 feet wide ex-               Any fractional number of holes is rounded off
Th mg about 8 feet beyond each end charge.                   to the next highest number. If a hole is too
    e method of placing charges is as follows:               small to accept the cratering charge, enlarge it
    a. Bore the holes 5 feet apart center-to-                by use of the detonating cord wick (para 98b).
           . Ine across the roadway. ' The end
cente r, In I'

       8 FT

                          Figure   107. Charge   placement    for deliberate   road crater.
                                                             of its depth and shape. It doeg, however, make
h ~' Place 80 pounds of explosive in the 7-foot              an excellent barrier for vehicles and small tanks
hOles and 40 pounds of explosive in the 5-foot                (fig. 108). The method described below forms
toes.      Two 5-foot holes must not be made next            a crater about .1 t/~ times deeper and 5 times
t~ each other. If they are so calculated. one of             wider than the depth of the boreholes and ex-
ad~m must be a 7-foot hole. The resulting two                tends about 8 feet beyond each end charge. The
    Jacent 7-foot holes may be placed anywhere               sides have a slope of 30° to 60° depending on the
 along the line.                                             soil. Craters formed by boreholes less than 4
  .. e PrIme all charges and connect them to fire            feet deep and loaded with charges less than 40
SImultaneously.     A dual firing system should be           pounds are ineffective against tanks. The fol-
 Used.                                                       lowing hasty cratering method has proved satis-
     d. Place a I-pound primer in each hole on top
 of the can for dual priming if the standard                     a. Dig all boreholes to the same depth. This
 Cfat ering charge is used.
   .     .                         '                          may vary from 2th to 5 feet, depending upon
 9 e. Stem all boreholes with suitable material.              the size of the crater needed. Space the holes 5
   O. Hasty Road Crater                                       feet apart center-to-center across the road .
     Although a hasty road crater takes less time                b: Load the boreholes with 10 pounds of ex-
.~~d less explosive for construction than a de-               plosive per foot of depth.
  l erate road crater,   it is less effective because                                                      101

 AGO 7258A
                           Figure   108.   Charge   placement   for haaty road crater.

   c. Prime the charges as for deliberate crater-
                                                                      three boreholes or always one less than
                                                                      the other row (2, fig. 109).
   d. Stem all holes with suitable material.                      (2) Make the boreholes on the friendly'
91. Special Cratering Methods                                         side 5 feet deep and load with 40
   a. Relieved Face Cratering J!ethod. This                           pounds of explosive, and those on the
demolition technique produces a trapezoidal-                          enemy side 4 feet deep and load with
shaped crater with unequal side slopes. The                           30 pounds of explosive.             .
side nearest the enemy slopes at about 25° from                   (3) Prime    the charges in each row sep-
the road surface to the bottom while that on the                       arately for simultaneous detonation.
opposite or friendly side is about 30° to 40°                          There should be a delay of detonation
steeper. The exact shape, however, depends on                        . of Ih to 11h seconds between' rows, the
the type of soil found in the area of operations.                      row on the enemy side being detonated
In compact soil, such as clay, the relieved face                       first. Best results will be obtained if
cratering     method will provide an obstacle                          the charges on the friendly side are
shaped as shown in 1, figure 109. The pro-                             fired while the earth moved in the first
cedure is as follows:                                                  row is still in the air. Standard delay
      (l) Drill two rows of boreholes 8 feet                           caps, may be used for delay detonation.
           apart, spacing the boreholes on 7-foot                 (4) Acceptable results may be obtained by
           centers. On any road, the row on the                        firing both rows simultaneously,       if
           friendly side will contain four bore-                       adequate means and sufficient time for
           holes. Stagger the boreholes in the                         delay firing are not available.
           row on the enemy side in relationship                         N  ?te.  While the procedure in (1), above,
           to the other row, as shown in 2, figure                     specIfies four boreholes on the friendly side
           109. This row will usually contain                          and three boreholes on the enemy side, more
                                                                       boreholes may be made if needed to crater
                                                                                                          AGO 7258A
                                                                          and branch lines of the row on the friendly
                                                                          side (detonated last) should be protected by
                                                                        _ a covering of 6 to 8 inches of earth.
                                                                  b. Angled Cratering }'lethod.    This method
                                                               is useful against tanks traveling in defiles or
                                                               road cuts where they must approach the crater
                                                               straightaway.   A line of boreholes is blasted or
                                                               drilled across a roadway at about a 45° angle,
                                                               and charged as in figure 110. Because of the.
                                                               unevenness of the side slopes, tanks attempting
                                                               to traverse an angled crater are usually halted
                                                                   c. Standoff Distance.  The standoff distance
                                                                for making the boreholes on unpaved roads
                                                                with M2A3 shaped charges should be 20 to 30
                                                               _inches. For paved roads, t~e standoff distance
                                                                should be about 36 inches. As the standoff dis.
                    ENr    y
                                                                st~nce is decreased, the depth of the open hole
                   -O0 Of                                       is decreased while the diameter is increased.

                                                                In any case, test hole should be made to ascer.

        f-        9?
                           0   0        DELAY
                                                                tain the optimum standoff distance.
                                                                  d. Blasting Permafrost.
                                                                     (1) Number    of boreholes         and   size   of
                                                                          charge. In permafrost,         blasting re.
        2. BOREHOLE             PATTERN                                    quires about 11/2 to 2 times the num.
                                                                           ber of boreholes and larger charges
                                                                           than those calculated by standard
        Figure     109.    Relieved    face   cratering.
                                                                           formulas      for    moderate     climates.
                                                                   •       Frozen soil, when blasted, breaks into
              w~der roads or to make larger craters.   They                large clods 12 to 18 inches thick and
              ~ ould be located and staggered, however,
                                                                            6 to 8 feet in diameter. As the charge
              In the same manner     as states in (1) above.
              To prevent misfires from the shock and blast                 has insufficient force to blow these
              of the row of charges on the enemy side                      clods clear of the hole, they fall back
               (detonated first), the detonating cord mains     __     -'linto-invhelltheblast       subsides .. Tests
                                                                           to determine the number of boreholes
                                                                            needed should be made before exten.
                                                                            sive blasting is attempted.       In some
                                                                            cases, permafrost may be as difficult to

                                       o                                    blast as solid rock.
                                                                     (2) ltfethods of making boreholes. Bore.
                               ~ __ -+---45°
                                                                            holes are made by three methods-
                     o                              ANGLE
                                                                            standard drilling equipment, steam
                                                                            point drilling equipment, and shaped
                                                                            charges. Standard drill equipment has
                                                                            one serious defect-the air holes in the
                                                                            drill bits freeze and there is no known
                                                                            method of avoiding it. Steam point
                                                                            drilling is satisfactory in sand, silt, or
                                                                            clay, but not in gravel. Charges must
                                                                            placed immediately upon withdrawal
                                                                            of the steam point, otherwise the area
         Figure    110.    Angled     cratering   method.                                                            103

AGO   1258A
         around the hole thaws' and plugs it.
                                                           temperature,    and conditions. of the
         Shaped charges also are satisfactory
                                                           original formation, the same size and
         for producing boreholes, especially for
                                                           type of crater is formed regardless of
         cratering.    Table XII shows the size
                                                           the standoff distance.   If the lake or
         of boreholes in permafrost      and ice
                                                           river is not frozen to the bottom and
         made by 1\13 and M2A3 shaped
                                                           there is a foot or more of water under
                                                           the ice, the water will rise to within
     (3) Explosives.    A low velocity explosive           6 inches of the top after the hole is
         like ammonium nitrate, satisfactory               blown, carrying shattered ice particles
         for use in arctic temperatures, should            with it. This makes the hole easy to
         be used, if available.    The heaving             clean. If the lake is frozen to the
         quality of low velocity explosives will           bottom, the blown hole will fill with
          aid in clearing the hole of large                shattered ice and clearing will be eX.
         boulders.    If only high velocity ex-            tremely difficult. Under some condi.
         plosives are available, charges should            tions, shaped charges may penetrate
         be tamped with water and permitted                to a depth much less than that indi.
         to freeze.    Unless high velocity ex-            cated in table XII.
          plosives are thoroughly tamped, they
                                                       (3) Surface charges. Surface craters may
         tend to blowout of the borehole.
                                                           be made with ammonium            nitrate
  e. Blasting Ice.                                         cratering charges or TNT, MI, M2, or
      . (1) Access holes. These are required for           M3 demolition blocks. For the best
            water supply and determining         the       effects, the charges are 'placed on the
            thickness of ice for the computation of        surface of cleared ice and tamped on
            safe bearing pressures for aircraft            top with snow. The tendency of ice
            and vehicles.     As ice carries much          to shatter more readily than soil
            winter traffic, its bearing capacity           should be considered when charges are
            must be ascertained rapidly when for-          computed.
            ward movements are required. Small         (4) Underwater charges.
            diameter access holes are made by
                                                         (a)   Charges are placed underwater by
            shaped charges. On solid lake ice, the
                                                               first making boreholes in the ice
            M2A3 penetrates 7 feet and the M3,
                                                               with shaped charges,         and then
            12 feet (table XII).      These charges
                                                               placing the charge below the ice. An
            will penetrate farther but the pene-
                                                               80-pound charge of M3 demolition
            tration distances were tested only in
                                                               blocks under ice 4th feet thick forms
            ice approximately 12 feet thick. If the
                                                               a crater 40 feet in diameter.     This
            regular standoff is used, a large crater
                                                               crater, however, is filled with float.
            forms at the top, which makes con-
                                                               ing ice particles, and at tempera.
            siderable probing necessary to find the
                                                               tures around 20° F freezes over in
            borehole. If a standoff of 42 inches               40 minutes.                .
            or more is used with the 1\12A3 shaped
            charge, a clean hole without a top           (b)   A vehicle obstacle may be crate red
            crater is formed. Holes made by the                in ice by sinking boreholes 9 feet
            1\12A3 average 3th inches in diameter,             apart in staggered rows. Charges
            while those made by the 1\13 average                (tetrytol or plastic) are suspended
            6 inches.                                          about 2 feet below the bottom of the
        (2) Ice conditions.     In the late winter             ice by means of cords with sticks
                                                               bridging the tops of the holes. The
            after the ice has aged, it growS weaker
                                                               size of the charge depends upon the
            and changes color from blue to white.
                                                               thickness of the ice. Only two or
            Although the structure of ice varies
            and its strength depends on age, air               three charges are primed, usually
                                                               one at each end and one at the mid.
                                                                                            AGO 7258A
                                                         feet deep and 4 to 40 feet wide may be blasted
             dIe, The others will detonate sympa-        in most types of soilS.. A brief outline of the
             thetically,   An obstacle like this         method "is. given below.
             may retard or halt enemy vehicles              a. Test Shots. Before attempting the actual
             for approximately 24 hours at tem- .        ditching, make test shots to determine the
             peratures around _24 F.                     proper depth, spacing, and weight of charges
                                                         needed to obtain the required results.     ~Iake
92 . Ct' ermg at Culverts
      A charge detonated to destroy a culvert not        beginning test shots with holes 2 feet deep and
 .more than 15 feet deep may at the same time            18 inches apart and then increase the size of
  Prod uce an effective road 'crater.
  ch                                     Explosive '     the charge and the depth as required. A rule
  1\ ~rges should be primed for simultaneous             of thumb for ditching is to use 1 pound of ex-
  Crlng and thoroughly tamped with sandbags.             plosive per cubic yard of earth in average soil.
  8tUlverts with 5 feet or less of fill may be de-           b. Alinement and Grade. Mark the ditch
  tn royed by explosive charges placed in the same       centerline by transit line or expedient means
  Canner as in hasty road cratering (para 90).           -and drill holes along it. \Vhen a transit or
  f oncentrated charges equal to 10 pounds per            hand level is used, the grade of the ditch may
. i~~t of depth are placed in boreholes at 5-foot         be .accurately controlled by checking the hole
  c lervals in the fill above and alongside the           depth every 5 to 10 holes and at each change in
    u vert.                                               grade. In soft ground, the holes may lie drilled
                                                          with a miner's drill or earth auger. Holes are
  93. Antitank Ditch Cratering
    ' a. Construction.      In open country antitank      loaded and tamped immediately to prevent
  d Itches ' are constructed to strengthen ' prepared     cave-ins and insure that the charges are at
  defensl ve pOSI IOns. As they are costly in time        proper depth. Ditches are sloped at a rate of
  b effort ,uc h' IS gamed If the excavation can
  and            m            '     .                     6 to 12 inches per 100 feet.      '
  e~ m~de by means of cratering charges. To be              c. Methods of Loading and Firing.
       ecbve, an antitank ditch must be wide enough            (1) Propagation method. By this method
                                                                  only one charge is primed-the     charge
  and dee p enoug h to stop an enemy tank. It may
.       Improved by placing a log hurdle on the                   placed in the hole at one end of the line
  ~~temy side and the spoil on the friendly side.                 of holes made to blast the ditch. The
  fro ches are' Improve d by digging the face on the              concussion from this charge sympa.
      lelndly side nearly vertical by means of hand-              thetically detonates the next charge
  t 00 s.                                                         and so on until all are detonated. Only
       b. Deliberate Cratering Method. The delib-                 commercial dynamite should be used
                                                                  in this operation.     The propagation
  89 .
  erate crat ermg method outlined in paragraph
                                                                  method is effective, however, only in
  tan~s ~dequa:e for the construction of heavy
                                                                  moist soils or in swamps where the
           dItches In most types of soil.
                                                                  ground is covered by several inches of
  d' c. Hasty Cratering Method. Ditches for me-
                                                                  water.     If more than one line of
     lum tanks may be constructed by placing 40
                                                                  charges is required to obtain a wide
  POunds of cratering explosive in 4-foot holes
                                                                  ditch, the first charge of each line is
     spaced 5 feet apart.       This makes a ditch ap-
                                                                  primed.     The primed hole is over.
  P       '
     roxlmately 6 feet deep and 20 feet wide. A
  hI'                                                             charged 1 or 2 pounds.
     eavy a n t't an k d itch may be constructed by
 ;cmg 50 pounds of cratering explosive in                 (2) Electrical method. Any high explosive
                                                                  may be used in ditching by the elec.
  i -toot holes, and spacing the holes at 5-foot
 t      ervals. The ditch will be approximately 8                 trical firing method which is effective
                                                                  in all soils except sand, regardless of
   geet deep and 25 feet wide (para 90).
                                                                  moisture content.      Each charge is
   4 Blasting of Ditches                                          primed with an electric cap and the
 to jn c~mbat areas, ditches may be constructed
                                                                  caps are connected in series.         All
 , ,~rain terrain flooded by the enemy or as
 t                                                                charges are fired simultaneously.
 Illlbal excava t'IOns for the preparation of en-
  renchments.      Rough open ditches 21/2 to 12                                                       105

 AGO 7258A
      (3) Detonating cord method.'In this ditch-                        ture content. Each charge is primed
          ing method any high explosive may,                            with detonating cord and connected to
          be used. It is effective in any type of
                                                                        a main or ring main line.
          soil, except sand, regardless of mois-

                         Section VII. LAND CLEARING AND QUARRYING CHARGES
95. Introduction                                              essary to remove stumps as well as trees.
   In military operations, construction jobs oc-              Stumps are of two general types, tap- and
cur in which demolitions may be employed to                   lateral-rooted (fig. 111). Military dynamite is
advantage. Among these jobs are land clearing,                the explosive best suited for stump removal.
which includes stump and boulder removal, and                 A rule of thumb is to use 1 pound per foot of
quarrying.    The explosi~es commonly used are                diameter for dead stumps and 2 pounds per foot
military dynamite and detonating ~cord. The                   for live stumps, and if both tree and stump are
quantity of explosive used is generally calcu-                to be removed, to increase the am(}unt of ex-
lated by rule of thumb. Charges may be placed                 plosive by 50 percent. Measurements are taken
in boreholes in the ground under or at the side               at points 12 to 18 inches above the ground.
of the target, in the target itself, or on top of                 a. Taproot Stumps. For taproot stumps, one
the target.    All charges should be tamped or                method is to bore a hole in the taproot below the
mudcapped, which is a form of light tamping.                  level of the ground. The best method is to place
96 •. Stump Removal                                           charges on both sides of the taproot to obtain
  In certain military operations             it may be nec-   a shearing effect (fig. 111). For best results,
                                                              tamp the charges.
                                                                  b. Lateral-Root Stumps.    In blasting lateral
                                                               root stumps, drill sloping holes as shown in
                                                               figure 111. Place the charge as nearly as possi-
                                                              ble under the center of the stump and at a depth
                                                               approximately equal to the radius of the stump
                                                               base. If for some reason the root formation
                                                               cannot be determined, assume that it is the
                                                               lateral type and proceed accordingly.
                                                               97. Boulder    Removal
                                                                 . In the building of roads and airfields or other
                                                                military construction, boulders can be removed
                                                                by blasting.    The most practical methods are
                                                                snakp.holing, mudcapping, and blockholing.
                                                                   a. Snakeholing Method. By this method, a
                                                                hole large enough to hold the charge is dug un-
                                                                der the bOUlder. The explosive charge is packed
                                                                under and against the boulder as shown in fig-
                                                                ure 112. For charge size, see table XIII.
                                                                   b. kludcapping    Method.    For surface or
                                                              . slightly embedded boulders, the mudcapping
                                                                method is very effective. The charge is placed
                                                                on top or against the side of the boulder and
                                                                covered with 10 to 12 inches of mud or clay (fig.
                                                                112). For charge size see table XIII.
                          FOR LATERAL-ROOTED        STUMPS         c. Blockholing Method. This method is very
                                                                effective on boulders lying on the surface or
         Pigure   111.    Stump   blasting   charges.
                  ,                                             slightly embedded in the earth. A hole is drilled
106                                                                                                      AGO 7258A
                                                                              nated in the bottom of a drilled borehole to form
      A. PLACEMENT             OF A SNAKEHOLE                 CHARGE          an enlarged chamber for placing. a larger
                                                                              charge. At times two or more springing charges
                                                                              in succession may be needed to make the cham-
                                                                              ber large enough for the final charge. Under
                                                                              these conditions at least 30 minutes should be
                                                                              allowed between firing and placing successive
                                                                              charges for the boreholes to cool.
                                                                                 b. Detonating Cord TVick. This is several
                                                                              strands of detonating cord taped together and
                                                                              used to enlarge boreholes in soils. One strand
                                                                              generally widens the diameter of the hole about
                                                                              1 inch.
                                                                                   (1) A hole is made by driving a steel rod
                                                                                        approximately 2 inches in diameter
 CRACK                                                                                  into the ground to the depth required
                                                                                        (para 41c) or by'means ofa shaped
      C. PLACEMENT             OF A BLOCKHOLE                 CHARGE                    charge.    According to the rule of
                                                                                        thumb, a hole 10 inches in diameter
                                                                                        requires 10 strands of detonating cord.
                                                                                        These must extend the full length of
                                                                                        the hole and be taped or tied together
                                                                                        into a "wick" to give optimum results.
                                                                                        The wick may. be placed into the hole
                                                                                        by an inserting rod or some field ex-
                                                                                        pedient.   Firing may be done elec-
            Figure     112.    Boulder   blasting        charges.                       trically or nonelectricallY. An unlim-
                                                                                         ited number of wicks may be fired at
. ~n top of the boulder deep and wide enough to                                          one time by connecting them by. a
  old the amount of explosive indicated in table                                         detonating cord ring m~in or main
 ;III.      The charge is then primed. put into the                                     line.
  orehole, and stemmed (fig. 112).                                                  (2) The best results from the use of the
                                                                                        detonating cord wick' are obtained in
 98. Springing Charges                                                                  hard soil. If successive charges are
   a. Definition and Method.    A springing                                             placed in the holes, excess gases must
 Charge is a comparatively small charge deto-                                           be burned out and the hole inspected
                                                                                        for excessive heat.
      Table XIII.       Charge    Size for Blasting          Boulders
                                    Pounds   of explosive    required          99. Quarrying
  Boulder   diameter    (ft)                                    Mudcl\Pplng       Quarrying is the extraction of rock in the
 --                            B1ockholin~    Snakeholing
                                                                    1          natural state. Military quarries, generally of
         1% (rare)                 %                %
                                                    %               Ph         the open face type, are developed by the single
         2                         %
                                   14               %.              2          or multiple bench method. See TM 5-332 for
         3                                                          3%
         4                          %            2
                                                 3                  6          detailed information.
         5                          %


  AGO 7258A
                                               CHAPTER 4

                                       DEMOLITION PROJECTS

                                     Section I.    DEMOLITiON         PLAN
                                                                    for the demolition.
 100. Scope                                                    (10) Estimate and sketch of security                          de-
   ,Thus far, this manual has been concerned                        tails required.
 WIth methods and techniques in the selection,           SITUAT10N   MAP   SKETCH   (INCLUDES   PRINCIPAL   TERRAIN    FEATURES,
 calculation, priming, placement and firing of           IMMEDIATE   AVENUES    OF APPROACH;     OBSERVATION   AND COVER,

 ex p I '
       oSIves on such materials as 'steel, concrete,     MAP   COORDINATES)

 ;OOd. and stone and in earth.        This chapter
. ~als with the problems of applying these tech-
 nIques to the conduct of demolitions projects.                                                                       1-

 101 . Reconno.ssonce to Develop Demolition
    ~. Information     Required.    Thorough recon-
 naIssance is necessary before an effective plan
 may be made to demolish a target as reconnais-
 ~ance provides information in ali areas related
  o the project. Before the demolition of bridges,
 ~ulverts, and road craters the following data
 IS p rovl'd e d by reconnaissance.
        (1) Situation map sketch (fig. 113) show-
             ing the relative position of the objects
             to be demolished, the surrounding
             terrain features, and the coordinates
             of the objects keyed to existing maps.                   Figure    113,     Situation    map sketch.
        (2) Side-view sketch of the demolition ob-
             ject. If, for example a bridge is to be        b. Demolition Reconnaissance Record. DA
              blown, a sketch showing the overall        Form 2203-R (Demolition Reconnaissance Rec-
              dimensions of critical members is nec-     ord) (fig. 115), together with appropriate
             essary (fig. 114).                          sketches, is used to report the reconnaissance
        (3) Cross section sketches, 'with relatively     of a military demolitions project. This form
              accurate dimensions of each member         and the actions listed in a, above, are intended
              to be cut (fig. 114).                      primarilY for road and bridge demolition. They
        (4) A bill of explosives, showing the            are also partiallY applicable to the demolition
              quantity and kind required.                of almost any other object. In certain in-
         (5) Sketch of the firing circuits.              stances, the report may require a security
         (6) List of all equipment required for the      classification.  The form is reproduced locally
  d ernolition.                                          on 8- by 10th-inch paper.
         (7) List of all unusual features of the site.    102. Demolition Orders
         (8) Estimate of time and labor required            a.. purpose.  Three commanders are usually
              to bypass the site.                         involved in the execution of a demolition proj-
         (9) Estimate of time and labor required                                                                              109

  AGO 7258A
                                                                               ABUTMENT WIDTH 35 F1;
                                                                               HARD SURFACED ROAD
                                                                               WIDTH 24 FT

                                             50 FT                                    NORTH BANK
                                   9 FT
                          WITH DIMENSIONS

                                                                                r- 8tN-}

                                         FIRING SYSTEM                      TENSION MEMBER
                              Figure   114. Drawing   0/   object to be demoliahed.

ect. These are the tactical commander with
over-all responsibility and authority to order                          the order to fire the demolition is'
the firing of the demolition, the commander of                          transmitted from himself to the com.
the demolition guard" and the commander of                              mander of the demolition guard and
the demolition firing party,   To assist the com.                       thereby to the commander       of the
manders in the execution of their responsibili.                         demolition firing party. In the event
ties, two demolition orders are used. These                             that no demolition guard is required,
are shown in figure 116, (Orders to the Demo.                           this channel must be established be-
Htion Guard Commander)           and in figure                          tween the authorized commander and
117, (Orders to the Commander, Demolition                             . the commander of the demolition fir-
Firing Party) (DA Form 2050-R). The pro.                                ing party.
cedures that follow are in accord with the
                                                                  (3) Insure that this channel is known and
agreement between the armed forces of NATO
nations and will be complied with by Depart.                          understood by all concerned, and that
ment of the Army units.                                               positive and secure means of trans-
                                                                      mitting the order to fire are es-
  b. Procedures. Each authorized commander,                           tablished.
or the tactical   commander     referred    to in a
above, will-                                                       (4) Specify the conditions for executing
                                                                       the demolition as contained in part V
      (1) Establish the requirement and assign
                                                                       of "Orders to the Commander, Dem-
          the responsibility   for a demolition
                                                                       olition Firing Party," and completing
          guard and a demolition firing party.
                                                                       part IV of the "Orders to the Dem-
      (2) Establish a clear cut channel whereby
                                                                       olition Guard Commander."
                                                                                                     AGO 7268A
                                                               DEMOLITION RECONNAISSANCERD:ORD
                                                                          (FM 5-25)
                                                              SECTION I - GENERAL                                                           4. TIME
                                                                               3. DATE
                                                    2. DML RECON REPORT NO.                                                                   ZIOO
       1. Fn.E           NO.                                                                             ,t,1   JUNE"        ~    ~
                                                                             1                                                          ORGANIZATION
                       Lfl/                                                                                 GRADE
                                                                 NAME                                                        9S-o/ CA/~~ :BN
       5.                                                                                                 {!"A-p-r;
                                 6 ffV                    -:r                8/i
                                                                                                                             -KeCbAJ               Se-<!-
       6. PARTY                                                                                            SFC-
          LEADER            C. GAY   JOe                                                                                               b-S7fl':a: S           r=
       7. MAP REFERENCE S TA-NTolV                                            I:~:r; ()()O                 ShEe:rNo
                                                                                                                10. LOCATION
                                                                                    TIME OBSERVED
       18. SITE AND OBJECT                                                   9.                                         '/ , (, ~9 '/50
              GTCft:"L..        TKIISS.         8fl,       f?6=-1i? ~R()5'            Z;LOO
       _ WHJ'Te
                           -rr: 1IS"~
                  GENERAL DJ;SCRIPrION
                                             olf/   H S,N"-L6
                                                      r I W'
                                                                                sPAAJ         STeeL        T1?IJ5
                                                                                                                     :e'! Fr:

               lrVS 5>      II> Fr.
                                   OF      SP/tN             hOFT.
                                                                          j(/IPTH  of     81f1P~
                                                                        ",F 6"'1>6-13'- .....eov.:                w/tTe12..
                                                                                                                                       ;( 0 FT'

                 OlVc!<t:Te  /t6UTMGN7S       3b- FT ~J(?t:.
        12.       NATURE OF PROPOSED DEMOLITION ~-r,+-no/C1                                               /1t:rltoP.          CUT   v~re:J~                  ~NP
             LOt<JG=R..           C!...!toRp            oN       80TH        ENPS             of      r~lJSS        oP     Tift: UPST~eAI'1                  SII::>,-=

             OF     T7fL=       .J3R/D6-G           •    .J)c~TRor                 S.oVTH           S!+DR(;.        It BUTMc:ttJT:

                                                                        SECTION II - ESTIMATES*                                                          I

                                                                            EXPLOSIVES "IimUIRED                                             e. roSE LIGHT-
                                         b. POUNDS                      c.         cAFS                                                      ms        0
         a. TYPFS                                                                    Nonelec- 0  CORD:;-() 0 Fr
                  TN,                          /<01-85                 Elec-    t{ tric
         CP.A~/HII"'fr.        CH (;.    ~ -l/t7        1.4 CH~S       tric
         14.      ~UIPMENT            ~UIRED                                                '16;<-1/(,4         ReEt..>           of     rl/'J.4/~     WI!?,;:'.

                  1- Z ~             ,4!tJ     rlf~c.I<

                  I-       S q ().q.o                           t;;t:r.


                                                                                              pERSONNEL                                            /'11--<
                           PERSONNEL AND TIME ~UIRED
                                                                                                            I    SQ~A-P
                                                                          S~ION         III        - REMARKS
         16.      UNUSUAL FEATURES OF SITE
                                                                                         !J ()AJ c:

             17. LABOR AND TIME ESTIMATED ~UIRED                                      FOR BYPASS

                                                                                                    and 15 before reconnaissance.
                  *Determine            'availability                of Items       13, 14,               d t on of this -.torm is obsolete.
              DA FORM 2203-R,                  1 Mar 67                                  PreviOUS         e i i

                                                          Figure      115.   Demolition            reconnaissance       record.

AGO   126SA                                                                                                                                                              111
      Serial         No.                         ~Security        Classificatian,                       __

                            ORDERS. THE nlUOLITION GUARD CCI!MA.NDER

                   Notes:    1'.   This form will be completed and signed before
                                   it is handed to the Commander of the Demolition

                             2.    In completing the form, all             spaces    must      either
                                   be filled  in or lined out.

                             :3.   The officer   empowered to order the firing                      of
                                   the demolition   is referred to throughout                      as the
                                   "Authorized Commander".
       From~                                           To.                                                  -

                                   PART I - PRELItiINARXINSTRUCTIONS
       l.a.         Description     of target                                                               _

          b.         Location:
                             and Scale
                    Map Na.IOO                                    ~Sheet      No.                          _
                     Grid Reference                                     ___

              c•     Codeword or codesign       (if   any) of demoli tian           target     •                _
       2. The Authorized Comrmnder is                                      _
          (give appointment only).    If this officer  should delegate his
          authori ty, you will be notified   by one of the methods shown
          in paragraph 4, below.

       :3 •                       FIRING PARTY has been/will
                   The DE1.lOLITION                                           be provided          by               _

        4.         All messages,     inclUding any codewords or codesign                     (if    any)
                   used in these     orders, will be passed to you by:

              a.     Normal cormnand wireless         net,   or

              b.     Special liaison officer wi th communications                   direct         to the
                     Authorized Commander, or

                             Figure 116. Orders to the Demolition Guard Commander. CD

112                                                                                                                     AGO 7258A
                                        CLASSIFICATION      (Cont'd)
            c.     Telephone by the Authorized         Conmnn , or

            d.     The Authorized               personally,
                                     CoIIIITaIlder                or

                              (Delete those NOTapplicable)

  Note:          All orders sent by message will be prefixed by the code-
                 word or codesign (if any) at paragraph l.c., and all such
                 messages must      be acknowledged.

                                            CLASSIFICATION       (contld)
                                          Figure   116_Continued. @


AGO 7268A

     323-561 0 - 68 - 8
                                     NATO - ~CLASSIFIED
                           PAHT II   - CPu\NGING    STATES OF RFADINZSS

  5. The denoli":tion lillbe prepared initiallJ' to the state of
     Readiness                b~r          h~ours o~          (date) •

      6.    On   arrival at the demolition site, you vdll ascertai~ from
             the co~~der     of the denolition firing party the esti[~ted
             tioe required to change from state "1" (SAFE) to state "2"
           . (Arn~ffiD). You will ensure that this information is passed
             to the Authorized Commander and is acknowledged.

      7. Changes in the state of Readiness from state "1" (SAFE) to
         State "2" (m,ffiD) or from State "2" to State "1" will be
         made only when so ordered b~ the Authorized Cormnander. How-
         ever, the demolition may be ~mD    in order to accomplish
         emergency firing when you are authorized to fire it on your
         OVID initiative.

      8.    A record of the changes in the state of Readiness will be.
            entered by you in the table below, and on the firing orders
            in possession of the commander of the demolition firing party.

      State of Readiness                Time & date                 Authority      Time f..c date
      ordered "1" (SAFE)                change to                                  of receipt
      or "2" (ARMED)                    be completed                               of order

                     If the order is transmitted by an officer in person,
                     his signature and designation will be obtained in the
                     column headed "Authority".
       9.    You will report completion of all changes in the state of
             Readiness to the Authorized Commander by the quickest means.

                         PART III    - ORDERS FOR FIRING           THE' D:El.'1OLITION

       10. The order for firing the demolition will be passed to you
           by the Authorized Commander.

                                     NATO - UNCLASSIFIED
                                         Figure   116-Continued.     @

                                                                                                    AGO 7258A
                                  HATO -
 m~cT.ASSIFIED (Cont'd)

                           PART III   _ OWERS FOR FIRING THE DD~~OLITIQN

        11.   On receipt of this order you will immediately pass it to the
              commanderof the demolition firing party on his demolition
              Orders form ("Orders to the commmder of the Demolition
              Firing Party").
        12.   Ai'ter the demolition haS been fired you will report the re-
              sults immediate~to the Authorized commander.

        13•   In the event of a misfire or only partially successrUl
              demolition you will give the firing party protectiort WItH
              such time as it has completed the demolition and report
              again after it has been completed.

                                 NATO _ UNCLASSIFIED (cant' d)

                                      Figure 116-Continued.   @


AGO 7258A
                                       NATO - UNCLASSIFIED
                                 PART IV - FMERGENCY FIRING ORDERS

            Notes:      1.     One sub-paragraph of paragraph 14 must be deleted.

                        2.     The order given herein can only be altered by the
                               issue of a new form, or, in emergency by the
                               appropriate order (or codeword if used) in Part V.

      14.a. You will order the firing     of the demolition                 only upon the
                 order of the Authorized COffimander.


           b.                   is
                 If the eneII\Y in the act of capturing the target , and/or
                         I you will
                 muni. tion            order the firing of the demol!tion on
                 your own ini tia ti ve •                                 .

                                 PART V - CODEWORnS (IF          USED)

                      Action to be taken                                 Codeword (if used)

      a         Change state     of Readiness from "1" to
                "2"               (See paragraph 7)

      b.        Change State of Readiness from "2" to
                "1"           (See paragraph 7)

       c        Fire The Demolition (see paragraph 10)

       d        Paragraph 14a is now cancelled.  You
                are now authorized to fire the demoli-
                tion if the eneII\Y in the act of
                capturing it.

                                     NATO - UNCLASSIFIED
                                       Figure   116-Continued.   @

116                                                                                           AGO   725BA
                           NATO -   UNCLASSIFIED (Cont'dl

                     PART IV - EMERGENCY FIRING ORDERS


      e.    Paragraph 14b is now cancelled.         You              codeword (if used)
            will order the firing of the demolition
            only upon the order of the Authorized

      f.    Special authentication instructions, if

                                    PART VI
            Signature of officer issuing these orders__ ---------

            Name (printed in capital letters)__ -----------------
            Rank__   -------Appointrnent.-----------------
            Time of issue_----hours         ,_--------(                    date)•

                              NATO _ UNCLASSIFIED           (Cont'd)

                               Figure   116-Continued   @


AGO 7258A
                                     NATO - UNCLASSIFIED
                          PART VII     -

                               OF THE DD\.!OLITION GUt\RD

      15.   You are responsible         for:-

            a. Commandf the demolition guard and the demolition firing
                 party.          '

            b.   The safety of the demolition from eneI!\Yattack,                 capture,
                 or sabotage.

            c.   Control of traffic         and refugees.

            d.   Gt ving the orders to the demolition firing                party in
                 moiting to change the state of readiness.

            e•   Giving the order to the demolition firing                 party in writing
                 to fire the demolition.

            f.   After the demolition, reporting                 on its effectiveness   to
                 the Authorized Commander.

            g.                                     i
                 Keeping the Authorized Cornnnndernformed of the operation-
                 al situation at the demolition site.

      16.   You \'lill acquaint yourself '\"Iith the orders issued to the
            Comrmnder f the Demolition Firing Party and with the instruc-
            tions given by him.

      17.   The Demolition Guard will be so disposed as to ensure at all
            time complete all-round protection of the demolition against
            all types of attack or threat.

      18.                  o
            The Commander f the Demolition Firing Party is in teclmical
            control of the demolition. Youwill agree with him on the
            si te of your Headquarters and of the firing point.   These
            should be together whenever practicable.    Whensiting. them
            you must give weight to the technical requirements of being
            able to view the demolition and have good access to it from
            the firing point.

                                          NATO- UNCLASSIFIED
                                         Figure lIB-Continued.    (!)

                                                                                              AGO 7258A
                                  lJATO -   llliCIASSIFIED (Cent' d)

                             PART VII   -

                                  OF THE DDJOLITION        GUARD
     19.    You will nominate your deputy forthwith and compile a
            seniori ty roster.   you will ensure that each man knows his
            place in the roster, understands his duties and knovro\Vhere
            to find this form if yOUbecome a casualty or are unavoidably
            absent.                                            to
                      The seniority roster must be made kno\'lI1 the
            Conunander of the Demolition Firing Party.
     20.    Once the state of readiness "2 AR,lED" has been ordered, either
            you or your deputy must always be at your Headquarters so
            that orders can be passed an immediately to the commanderof
            the Demolition   Firing Party.

                                        NATO _ UNcLASSIFIED        (Cent' d)

                                   Figure 116_Continued.   @


AGO 7258A

                                                                                                            SERIAL NUMBER
                     ORDERS TO THE COMMNDER, IJEM)LITION FIRIN1                    PARrY

       mTE:       Parts   I, II and III will be completed       and signed    before              this     form  is handed to
                  the corrrnander of the Demolition     Firing   Party.    Paragraphs                4 and 5 can     only be
                  altered    by the authority issuing     these orders.     In such               cases     a new form will
                  be issued    and the old one destroyed.
       .FROM:                                                             TO:

                        PART I - ORDERS FOR ffiEPAROO                AND CHAffiItD     THE DEM::lLITION TARGET
       1a.    DESCRIPT'ION

       b.                                        LOCATION
                                                     \~NJ.               IGRID    RErnlENCE
                                                                                                          c. CODE WORD OF DEMOLI-
                                                                                                          TION TARGEr (If any)

        d. AITACHlill PH£JI'CGRAPHS AND SPfl;IAL               mHNICAL     INSrnUCTIONS

      - 2. 1'H1::DtMOLITION GUARD IS BErN.i PROVIDED BY (Uni t)

                                  'BY                       HOURS ON (Date)
              grATE OF READINE33           TIME AND DA1E
                    ORDERED                 ClWGE ro BE           AUTHORITY       TIME AND DA1E OF
          "1 (SAFE)" or "2 (ARMED)"          COMHElliD                             RECEIPT OF ORDER

       NOTE:      All orders   received    by message           will be verified     by the code word         at Paragraph     Ic.
                  If the order    is transmitted     by         an officer    in person,   his signature        and designation
                  will be obtained      in the Column           headed "Authority".
                                                 PART          II - ORDERS FOR FIRIN}
              The officer  issuing thes~ orders   will strike.   out the s~paragraphs  of Paragraphs       4',
              and 5 which are not apphcable.     When there    is a derroll hon guard, Paragraph    4' will
              always be used and Parap;raph  5 will always be struck       out.
         b. YOU WILL FIRE THE DOOLITION AT                        HOURS ON (Date)
                                                          HAS SIGNED PARPGRAPH 8 BELOW.
                    EMERGOCY FIRUG             ORDERS (ONLY applicable           when there   is NO demolition        guard)

             4 ABOVE.
             CAPI'URIID IT.
        DA l"OHM 2050-R,      1   ruv    0I
                                                                                                             SECURITY CLASSIFICATION

                           Figure       117.    Orders       to the Commander,       Demolition   Firing     Party.   CD

120                                                                                                                                  AGO 7258A
             See Paragraph 13.)
      SIGNATURE OF OFFICER ISSUOO                  NAME (In   capitals)                             TIME OF              DATt: OF ISSUIi
      THESE ORDERS                                                                                  ISSUE
                                              PARI' IV - ORDER TO FIRE
        8.     BEOO     EMPOWERED TO DO SO, I ORDER YOU TO FIRE NOW '!BE DEMOLITION DESCRlBlll                                   IN
            PARAGRAPH 1.
       SIGNATURE                                   NAME (In   capitalS)                             TIME                 DATE

                         PART V _ GENERAL INSlROCTIONS           lRead    These      Instructions           carefull


       10.     YOU SIToo  OF THE FIRING TIlE C<MIANlJ
               THE MUSr UNDERSTAND THAT POINI'.                                                     GUARD
                                                      ER OF TIlE DOOLITION                                    (where     there        is one)

                a. RESPONSIBLE FOR:                                                                     SITE.        (You are         there-

                b.    fore under his corrmand. )
                      PREVENTINJ TIlE CAPI'URE OF '!BE DEMlLITION            SITE,       00    INI'Effi'ERENCE       BY TIlE     EN!MY WI11I
                      DEMOLITION    PREPARATIONS.
                d     CONTROLLIN}
                      GIVING YOU     ALL TRAFFIC CHANJE TIlE
                                    TIlE ORDER TO AND REFlJ}EES.STATE OF READINES3 FRClI! "I (SAFE)" TO "2 (A!WD) ,


         12.    IDENTIFY HIM.
                IF YOU GEl' ORDERS TO FIRE, ()l1llR THAN 'nIOSE LAID DOWNIN pARAGRAPl! 4, YOU SlDULD         .

         13.    TIlE REPORT TO YOUR UNIT COMI\ANDIID OFFICER, AS CALLED FOR IN                              pARAGRAPl!     7, SlIDULD'
                CONTAIN THE FOLLOW!NJ INFORMATION (where applicable):
                 b.    MAP REFERENCE.
                         ESTIMATED WIDTH OF GAP) IN CASE OF A BRIIX}E
                         NUMBER OF spANS OOWN )
                         MINES LAID.
                 e.    SKETCH SHOWIID EFFECT        OF DEMOLITION.

                                                        Figure 111_Continued.              @


AGO   7258A
   c. Orders to the Demolition Guard Com-                         are prepared and securely fixed to the
mander. The authorized commander completes                        target and are safe against premature'
and signs this form. The order IS written in                      firing. All firing circuits and acces-
seven parts, each of which is self-explanatory.                   sories have been checked, are in proper
   d. Orders to the Commander, Demolition                         operating condition, and are ready to
Firing Party.       In addition to those items listed             be attached to charges.     If detonating
in b above, the authorized commander desig-                       cord is used it may be attached to
nates the unit or individual responsible for the                   demolition charges;     however, deto-
preparation of these orders.        This unit or in-               nators will not be attached to detonat-
dividual will complete and sign parts r through                    ing cord ring mains or main lines until
III and pass the order to the commander of the                     the state of readiness is changed to
demolition firing party.       Part IV will be com-                "armed."
 pleted upon detonation of the demolition (fig.               (2) "2 (Armed)."        The demolition        is
 117).                                                             ready for immediate firing. The risk
    e. Definitions.    The states of readiness (safe               of premature detonation is accepted.
 and armed) referred to in part I of the Order             f. Disposition of Orders. After the demoli-
 to the Commander, Demolition Firing Party,             tion has been fired, one copy of the orders will
 and in part II of the Order to the Demolition          be retained by the headquarters of the issuing
 Guard Commander, are described as follows:             authority and one by the commander of the
       (1) "1 (Safe)."        The explosive charges     demolition firing party.
 103. Types of Military Demolitions       though enemy interference might prevent com-
    There are three types of demolitions applica-       pletion of the job. Each charge is primed as it
 ble to tactical situations--reserved, deliberate,      is placed; for if charges are all placed first and
 and hasty.                                             then primed, it is possible. that enemy inter-
    a. Reserved Demolitions.   These are specifi-       ference prior to the act of priming might stop
 cally controlled at a command level appropriate        the work before any damage is done. The use
 to the tactical or strategic plan. Reserved            of dual detonating cord ring main lines and
 demolitions are usually in place, "ready and           branch lines is recommended for all frontline
 waiting," in the "safe" condition.                     demolition projects (para 64-70).

     b. Deliberate Demolitions. Deliberate demo-         104. Nuclear     Weapons      Demolitions
 litions are used when enemy interference dur-
                                                           Atomic demolition munitions        (ADM) may
 ing preparations      is unlikely and there is
                                                        be effectively employed to create obstacles and
 sufficient time for thorough reconnaissance and
                                                        to destroy and deny military facilities or in-
 careful preparation.      Deliberate preparation
                                                        stallations.   They have the capability of creat-
 permits economy in the use of explosives, since
                                                        ing large radioactive        craters    with little
 time permits accurate calculation and positive
                                                        preparatory effort. The residual radiation and
 charge placement to obtain the effects required.
                                                        fallout hazards require consideration; however,
    c. HW3ty Demolitions. Hasty demolitions are         the use of small yields minimizes the fallout
 used when time is limited and economy of ex-           hazard and area of residual contamination.     The
 plosives is secondary to speed. In all cases,           ODl\I, like conventional hand-placed charges,
 common sense and good judgment must be ex-              has a primary advantage of no delivery error,
 ercised to prevent waste. In the preparation            which permits the use of minimum yield for a
 of demolition projects in forward areas where           given target.   This is of particular importance
 a surprise raid by hostile forces is possible, a        in producing' craters or for destruction through
 priority should be given to each charge. Al-            cratering effects since the radius of cratering
 though this procedure is relatively time con-           effects of atomic weapons is relatively small in
 suming, it causes maximum damage to the                 comparison with other effects. No further in-
 project in relation to the time required, even          formation, see FM 5-26.
  122                                                                                                 AGO 725M
                                                                sites. Thus, for a demolished bridge, the
  105. Supplementing             Demolition .Obstacles          dropped spans and abutments should be mined
  f Nuisan ce mmmg and charges with delay
                          .,                                    to impede removal or recovery; suitable sites
  e~ses are a very potent means of increasing the             . for a floating bridge or ford should be mined
       .ects of demolition projects.        The area to be      to prevent ready use; and locations likely to be
  ~lDed should include the facility                    to be    selected for material storage, equipment. parks,
    ;stroyed,        the ground where a replacement             or bridge unit bivouacs should also be well
    sructure or remedial work will likely be per-               mined and booby trapped.
  f ormed , wo rIng party bIvouacs, and alternate
                       k'           .
                                           Section III. BRIDGE DEMOLITION
                                                                             of broken and twisted material. The
                                                                              destruction of massive bridge com-
   106. Extent of Demolition
                                                                              ponents,     however,     requires   large
   . ~here is no rule of thumb or regulation to
                                                                              expenditures of explosive, time, equip-
   IndIcate th e op t'Imum extent of demolition of
  b .
                                                                              ment, and effort that may not be
      rIdges. It is determined after investigation
                                                                              profitable.     In many. cases on major
   and ana I'ySIS of specific conditions.                                     bridges, the destruction of any com-
. dea. C.0;nplete Bridge Demolition. Complete                                 ponent that can easily be replaced may
   ab~olitlOn le~ves nothin? of the old bridge suit-
                                                                              not be justified.
   th ~or use m a new bridge.              Debris is left on            (2) Factors determining           the extent of
   h e site where its removal will require much                               destruction.      Factors that determine
      azardous work before any kind of crossing                               the extent of destruction needed for
   can b Installed..            However       when enough
                                                                              a project are as follows:
   t em 0 rt'Ion IS accomplished to ' force the enemy
   d         I                                                             (a) The tactical and strategical situa-
     o select another site for a temporary bridge                                tions that indicate the length of
   as a su b s t't ute for the damaged bridge further                            time the enemy must be delayed,
    demort' IOn IS unnecessary.
             1        .                   Too a permanent
                                                     '                           the time available for demolition,
    st ru .ct ure IS not likely to be replaced in kind
    d               .                         '
                                                                                 and the extent of denial to be ac-
    . UrIng wartime.         However, where the terrain
 .is     such that the existing bridge site is needed                            complished.
                                                                           (b) The likelihood that friendly forces
       or a new structure, even a temporary one                                  may reoccupy the area and require
    dem ?rt'IOn In greater
              1         .             proportions     may be'
                                                                                  the use of the bridge.
    JustIfied.                                                              (c) The results to be obtained by the
         b. Partial Demolition.                                                   expenditure of labor and materials
            (1) Method.       Bridges are generally de-                           compared with the results that may
                 molished to create obstaCles that delay                          be obtained elsewhere with'the same
                  the enemy. This seldom requires com-                            effort.
                  plete destruction.       Unless a denial                  (d) The manpower,           equipment, and
                  operation is in effect, the demolition                          kinds and quantities of explosives
                  method chosen should permit the eco-                             available.
                  nomical reconstruction        of the bridge
                  by friendly troops at a later date.              107. Parts of Fixed Bridges
                   Frequently the necessary delay can be             The ordinary fixed bridge is divided into two
                   obtained by only blasting a gap too             main parts: the lower part or substructure,
                   long to be spanned by the prefabri-             and the upper part or superstructure (fig. 118).
                   cated bridging available to the enemY.            a. Substructure.         The substructure consists
                   This gap should be located where the            of the parts of the bridge that support the
                   construction of an intermediate sup-            superstructure.        There are two kinds of sup-
                   port is difficult or impossible. A high         ports: end supports or abutments and inter-
                   and relatively slender bridge com-              mediate supports, or piers or bents. The parts
                    ponent may be demolished by cutting            of the substructure are--
                    one side so that it topples into a mass                                                            123

   AGO   7258A
                                        FLOOR BEAM




                                         Figure   118. Parts 01 fixed bridge.

      (1) Abutment.     The ground supports at
                                                                        bents constructed     as a unit, or a
          the ends of a bridge are called abut-
                                                                        single pile or trestle bent.
          ments. These may be constructed of
          concrete, masonry, steel, or timber                    b. Superstructure.    The superstructure    in-
          and may include retaining walls or an               cludes the flooring, stringers, floor beams, and
          end dam.                                            any girders or trusses that make up the total
                                                              part of the bridge above the substructure    (fig.
      (2) Footing.    A footing is that part of               118) .
          any bridge support that rests directly
                                                                    (1) Span.
          on the ground.    It distributes the load
          over an area wide enough to keep the                         (a). Simple.     Simple spans have string-
          support from sinking into the ground.                              ers that extend only from one sup-
      (3) End dam. An end dam is a retaining                                 port to the next.
          wall of concrete, wood, or other ma-

                                                                       (b)   Continuous. Continuous spans have
          terial at the end of a bridge that sup-
                                                                             beams that extend over one or more
          ports the bank and keeps the approach                              intermediate supports.
          road from caving in.
      (4) Intermediate       support.   An intermedi-               (2) Truss. A truss consists         of     these
               ate support is a support placed be-                      principal elements:
               neath a bridge between the abutments.
                                                                       (a)   Lower chord.    The lower chord is
               It may be a pier of masonry or con-
                                                                             the lower member in a panel of a
               crete, cribbing, several pile or trestle
                                                                             truss that runs parallel to the deck.
124                                                                                                      AGO 7258A
                                                                  porary intermediate piers that might
          (b)   Upper chord. The upper chord in-                  be erected to repair the structure will
                cludes the upper members in the                   be located where they will block traffic
              panel.                                              on the railroad or canal.
       (3) Stringers.   Stringers run longitudin-             (5) Any long steel members that require
           ally with the bridge and directly sup-                 cutting in only one place to demolish
           port the deck.                                         the bridge should be further damaged
       (4) Deck and tread. The deck is the floor                  to prevent their ready salvage by re-
           of the bridge and the tread, the top                   cutting or splicing. It is not neces-
           surface material.                                      sary to cut such members completely
                                                                  in two at other points to accomplish
 108. Planning        Bridge Demolitions                          this. A number of small charges
 r a. Structural Characteristics.        The demoli-
             properly located will damage the up-
  ~o.n of bridges must be carefulIy planned, as                   per flange, the lower flange, and the
    rIdges have a great variety of superstructures                web, which will make repair difficult
  ~ade of steel, timber, or masonry and various                   and uneconomical. The twisting of
  TyPes.of substructures made of these :materials.                 such members in dropping the span
. dhe SIze and placement of the charge, therefore,                 and any other feasible method of fur-
  b epends on the characteristics of the individual                ther destruction should also b~ con-
    rIdge structure.                                              sidered.
      b. General Procedures.      Some general pro-           (6) The nature of the terrain under the
  :edures apply to most bridge demolition pro-                    bridge is of great importance to the
  Jects; for example:        if charges are placed                success of the demolition.     If the dis-
  under the bridge roadway, special precautions                   tance from the river bed, for example,
  must be taken to insure that the charges will                   to the bridge is adequate, the weight
  ~ot be shaken loose or initiated by traffic on                  of the bridge may be exploited to
   he bridge.      The following general points ap-               assist in its destruction (fig. 127).
  ~l~ to the demolition of most or alI of the
    rIdge structures mentioned and described be-          109. Destruction of Substructures
  1cw.                                                      a. Concrete and Masonry Abutments.
         (1) Hasty charges, which must be placed               (1) Charges in fill behind abutment.   The
              first because of enemy interruption,                 placing of charges in the fill behind
              should be located carefully, if possible,            an abutment has the advantages of
              so that they may be included later on                economy in the use of explosives and
              into the deliberate preparation of the               of concealment of the charges from
              bridge.                                              the enemy until they are detonated.
         (2) It is often possible either to economize              This method also has its disadvant-
              on the use of explosives or to improve               ages, as the charges are difficult to
              the thoroughness of the demolition by                place.   \Vhere speed is required,
              blasting several times rather than only              charges are not placed behind the
              once. When conditions permit, this                   abutment if the fill is known to
              procedure should be considered.                      contain large rockS. If the bridge ap-
          (3) Tension members are more difficult to                proach is aJ1 embankment, the most
              repair than compression members, be-                 practical method may be to place ex-
              cause the latter may sometimes be                    plosive charges in a tunnel driven
              replaced by cribbing while the former                 into the side.
              almost always require steel riveting               (a) Abutments 5 feet or less in thick-
              or welding.     Thus tension members                 . ness and 20 feet or less in height
               should be given priority.                                (fig. 119). Such abutments are de-
          (4) When bridges over railways or canals                     molished by a line of 40-pound
               are to be destroyed, the demolition                     cratering charges placed on 5-foot
               should be so planned that any tem-                                                       125

  A.GO 7258A
         centers in holes 5 feet deep and 5                              These charges are calculated bY
         feet behind the face of the abutment                            means of the breaching formula,
          ("triple-nickel-forty").. The first                            P     =
                                                                               RaKC (para 86a), using the
         hole is placed 5 feet from one side                             abutment thickness as the breaching'
         of the abutment and this spacing is                             radius R. The charges are placed
         continued until a distance of 5 feet                            at a depth equal to or greater than
         or less is left from the last hole to                           R. The number of charges and
         the other side of the abutment. The                             their spa~ing are determined by the
         formula for computing the number                                                        W
         of charges is                                                    formula N           = -.
                 W                                                                         2R
          N = - - 1, where N =
number of                          (2) Combination       charges. A combination
                5        .                                             of external breaching charges and fill
          charges and W the width of the                               charges may be used to destroy abut.
          abutment.    If the wing walls are                           ments more than 20 feet high. Breach.
          strong enough to support a rebuilt                           ing charges placed along the bottom
          or temporary      bridge, they too                           of the abutment face should be fired
          should be destroyed by placing                               simultaneously      with the charges in
          charges behind them in a similar                             the fill behind the abutment.      These
          fashion.                                                     fill charges may be breaching chargeS
      (b) Abutments more than 5 feet thick                             as explained in (1) (b) above, or the
          and 20 feet or less in height. Such                          "triple-nickel-forty"    charges depend.
          abutments are destroyed by breach-                           ing on the abutment thickness.      This
          ing charges placed in contact with                           tends to overturn and completely de.
          the back of the abutment (fig. 120).                         stroy the abutment.

         40-   LB CHARGES

                  Figure   119.   Charges   placed in fill behind reinforced       concrete   abutment
                                                 5 feet thick or le88.

126                                                                                                      AGO 7258-"
                           20 FT OR LESS
                           IN HEIGHT

    REAR FACE        ONLY

      N   =

                        Figure 120. Charge. placed in {ill behind reinforced concrete abutment
                                                   more than 5 feet thick.
                                                                             either by internal or external charges
                                                                              (fig. 121). Internal charges require
  b. Intermediate Supports.I
                                                                             less explosive than external charges,
     (1) Effectiveness.    The destruction of one
                                                                             but because they require a great
          or more intermediate supports of a
                                                                             amount of equipment and time for
          multispan bridge is usually the most
          effective method of demolition (fig.                               preparation, they are seldom used un-
          121) . The destruction of one support                              less explosives are scarce or the pier
          will collapse the spans on each side                               has built-in demolition chambers. The
          of it, so that destruction of only al-                             number of charges required is cal-
          ternate intermediate supports is suffi-                                                         lY
          cient to collapse all spans. For repair                            culated by the formula N     -
                                                                                                        = 2R   (para
          this will require either the replace-
          ment of those supports or the con-                                 87b).    The size of each charge is
          struction of long spans.                                           calculated by the breaching formula,
       (2) Concrete and masonry piers. Concrete                              p =R3KC (para 86a).
               and   masonry    piers    are     demolished                                                      127

AGO   7258A
       (a) Internal charges. Plastic (C3 or
            C4), dynamite, and other explosives
            are     satisfactory     fo"r internal
            charges.     All charges of this type
            should be thoroughly tamped with
            blunt wooden tamping sticks, not
            with steel bars or tools. If there                        •                    •

            are no demolition chambers, charges

            are placed in boreholes, which are                  ------.
            blasted by means of shaped charges
            or drilled with pneumatic or hand
            to"ols. A 2-inch diameter borehole
            holds about 2. pounds of explosive
            per foot of length or depth. The
            steel reinforcing bars make drilling
            in heavily reinforced concrete im-                       •• •                               CHARGES
            practical, however.                                           •
        (b) External charges. External charges         ---       -   ----    -_   ..   -
             may be placed at the base of a pier
             or higher and spaced not more than
             twice the breaching radius (para
             86b) apart.      All external charges
             should be thoroughly tamped with
             earth and sandbags if time and the
             size, shape, and location of the tar- .
             get permit.
  110. Stringer Bridges
      a. Use. The stringer bridge (fig .. 122) is
  the most common type of fixed bridge found in
  most parts of the world. It is frequently used
  in conjunction with other types of spans. The
  stringers are the load-carrying members, while
 the floor is dead load. Stringers may be tim-
 ber, concrete, rolled steel sections, or plate
      b. Simple Spans.   In simple span stringer
. bridges, the stringers extend only from one
  support to the next. The method of destruc-
  tion for this type of superstructure   is to place
                                                       Figure   121.        Charges            placed on intermediate   supports.
  the charges so that they cut the stringer into
  unequal lengths in order to prevent reuse (fig.       ers, or trusses may be identified readily because
   122).                                                they are either the same depth or deeper over
      c. Continuous Spans. Continuous spans have       .piers than elsewhere, and there is no break or
  continuous lateral supports that extend over          weak section over the supports.        The super-
  one or more intermediate supports.        Because     structure. may be demolished by cutting each
  the spans are stiffer over piers than at mid-         member in two places between supports and
   span, they may frequently remain in place even       then dropping completely the portion between
  though completely cut at midspan.         Steel or     the cuts. Also, the span may be cut in un-
   reinforced concrete is commonly used for such        equal portions on the sides of the support for
   lateral supports.  Continuous steel beams, gird-     overbalancing    and falling.    Continuous con-

 128                                                                                                                    AGO 725M
                                                               111. Slab Bridges
                                                                   The superstructure of a slab bridge consists
                                                                of a flat slab support at both ends (fig. 123) .
                                                              . This is usually made of reinforced concrete, but
                                                                may also be of laminated timber or a com..
                                                                posite section of timber with a thin con-
                                                                crete wearing surface.      If they. are simple
                                                                spans, the superstructure may be destroyed by
                                                                the use of a single roW of charges placed either
                                                                across the roadway or underneath the span.
                                                                The breaching formula is used for reinforced
                                                                concrete slabs; and the timber-cutting (external
                                                                charge) formula is used for laminated timber.
                                                                On reinforced concrete slabs, the charges are
                                                                placed twice the breaching radius apart; and
    Figure       122.   Placement  of charges   on steel
                         stringer bridge.                       on laminated timber, twice the slab thickness
                                                                 apart.   Continuous slab spans must be cut in
crete T-beams or continuous concrete slab                        two places to insure the dropping of the slab
bridges may be recognized by the absence of                      or cut in places over the support to provide
construction or expansion joints over the sup-                   overturning by unequal weight distribution.

                                      Figure 1~S. Placement 0/ charges on Blab bridg~.

 112. Concrete T.Beam Bridges                                      a. Charge Placement on Simple Span. Sim ..
                                                                pIe span T-beam bridges are destrC')'cd by
    A T-beam bridge isa heavily reinforced con-                 explo~ives calculated and placed by the pressure
 crete stringer bridge with the floor and stringer              formula or breaching formula.
 made in one piece. The floor acts as part of the
 beam. This type is heavily reinforced. T-beam                     b. Charge Placement    on Contin1l01lS Span.
 bridges are generally simple span or continuouS                                                              129

 AGO     7258A
Continuous span T-beam bridges are destroyed                must be studied to determine the function of
by breaching.    Charges   calculated  by the             . the members.    Otherwise the charges may not
breaching formula are usually placed under                  be properly placed.
the deck in order to use the thickness of the
beam R. Continuous T-beam bridges may be                   114.   Truss Bridges
recognized by the haunching or deepening of                   a. Description.      A truss is a jointed frame
the section adjacent to the interior supports.             structure consisting of straight members (steel
According to conditions, it may be necessary               or timber) so arranged that the truss is loaded
to demolish the piers, demolish the junction               only at the joints.      Trusses may be laid below
between span and pier, or remove all spans by              the roadway of the bridge (deck-type trusses)
cutting them at approximately one-quarter of
                                                           or partly or completely above the roadwaY
their length from each end between supports.                (through-type trusses).
Breaching charges are used in all these cases.
                                                               b. Single Span Trusses.      Single span trusses
They may be placed on the roadway, or under-
                                                           extend only from pier to pier, usually having
neath it if the bridge must be used after the
                                                           a pin joint on one end and a sliding connection
charges have been prepared (fig. 124).
                                                           at the other.        Simple span trusses may be
                                                           destroyed by any of the following methods:
                                                                  (1) Cut the upper chord and lower chords
                                                                       at both ends of one truss in each span
                                                                      on the upstream side. This causes the
                                                                      bridge to roll over; thereby twisting
                                                                      the other truss off its support (rota-
                                                                       tion method).       The height of the
                                                                       bridge above the riverbed, however,
                                                                       must permit this. Place the charges.
                                                                       on the upper chord so that upon firing .
  Figure   1f-'.   Placement 01 charges   on continuous                the severed upper member will not
                        T-beam span.
                                                                       h :.tng on the lower member and the
                                                                       gap will extend the width of the road-
113.   Concrete Cantilever         Bridges                             way (fig. 127). If the truss is too
   a. Description.    Concrete cantilever bridges                      small and too light to twist free, both
are identified by the construction joints that                         ends of both trusses on each span
appear in the span but not over the piers.                             should be cut or the method described
Figure 125 shows a cantilever bridge with a                            in (2) below should be used.
suspended span and figure 126, a cantilever                       (2) Cut the upper chords, lower chords,
bridge without a suspended span.                                       and diagonals of both trusses and the
   b. Concrete Cantilever Bridges with Sus-                            roadway midspan (fig. 128) .. This is
pended Span. The superstructure           of this                      a more complete demolition and makes
bridge may be demolished by cutting each                               the reuse of the truss extremely diffi-
cantilever arm adjacent to the suspended span.
If a large gap is desired, the cantilever arms                    (3) Cut both trusses into segments (fig.
should be cut in such a way as to drop the
cantilever arms and the suspended spans (fig.                  c. Continuous      Span Trusses.      Continuous
125).                                                       span trusses are usually extended over two
                                                            spans, rarely over ~three. The heaviest chord
   c. Concrete Cantilever Bridges without Sus-
                                                            sections and the greatest depth of truss are
pended Span. As in the bridges above, the
                                                            located over the intermediate       supports.   One
superstructure     of a cantilever bridge without           method of demolition is shown in figure 130.
suspended span is demolished by destroying
                                                            In general, aside from the exact location of
the cantilever action and unbalancing the can-              charges, the methods given for the destruction
tilever arms (fig. 126). A bridge of this type
                     ,                                      of simple span trusses are applicable to con-
130                                                                                                  AGO 7258A
               Figure   125.   Pla,cement   of charges on concrete cantilever   bridge with suspended   span.

                                                                  Span.    Cantilever truss bridges with suspended
tinuous spans.    Care must be taken to make                      span are invariably major bridges having sin-
the cuts so that the bridge becomes unbalanced                    gle suspended spans. The suspended spans are
and collapses.                    .                               hung from the ends of adjacent cantilever arms
                                                                  by means of hinges, hangers, or sliding joints.
115.     Cantilever     Truss Bridges                             Cutting at these junctions causes these spans to
   a. Description.  Cantilever truss bridges ob-                  drop out of the bridge (fig. 131). These may
tain their strength by having a much deeper,                      be identified by a thorough study of the bridge
stronger beam section over the piers, or in                       structure.   Additional steel members may be
effect, two "arms" that reach partially or com-                   provided for stabilization but carry no load.
Pletely across the adjacent spans. As canti-                      The cantilever arms may also be destroyed by
lever truss bridges .are a modification or                        the method described in c below.
refinement of continuous truss or continuous
beam bridges, the demolition methods given in                       c. Cantilet'er Truss Bridge lVithout Sus-
Paragraphs 112 and 114 apply.                                     pended Span. To. destroy a cantilever truss
   b. Cantilever Truss Bridges with suspended                                                                   131

AGO    7258A
                     Figure   126.   Placement of chargs on conceret   cantilever     bridge
                                            without suspended span.

not containing a suspended span, the method
                                                                    supports    to the highest     point on the
shown in figure 132 is recommended.     The top                     arch.
and bottom chords are cut at any desired point,
and the. bridge is cut through near the joint at              (4)   Crown.          The highest   point   on the
the end of the arm in the same span. Another
method of destruction      is to cut completely               (5)   Abutments. The supports of the arch.
through the bridge at any two points in the                   (6) Haunches.    Those portions      of the
same span, thereby dropping out the length of                     arch that lie between the crown and
bridge between the two cuts.                                      the spring lines.              .
                                                              (7) Spandrels.     The triangular-shaped
116. Arch Span Bridges
                                                                  areas between the crown and abut-
   a. Component.fJ. A few of the components of                    ment and above the haunches.
bridge arches are described below and illu-
                                                            b. Filled Spandrel Arch.     A filled spandrel
strated in figure 133.
                                                         arch consists of a barrel arch (comparatively
      (1) Span. The horizontal distance from
                                                         short span) supporting an earth or rubble fill
          one support of an arch to the other
                                                         between the retaining walls. The arch is the
          measured at the spring line.
                                                         most vulnerable at its crown, where it is the
      (2) Spring lines.   The points of junction
                                                         thinnest and the earth fill is usually only a foot
          between the arch and the supports.
                                                         or two thick. Filled spandrel arches are con-
      (3) Rise. The vertical distance measured
                                                         structed of masonry (stone or brick), rein-
          from the horizontal line connecting the
                 ,                                       forced concrete, or a combination of these
                        Figure   127.   Bridge   destruction    aided by its own weight.
                                                               charges should be placed there. The presence
materials.    They may be destroyed by either                  of demolition vaults is usually revealed by the
crown or haunch charges.                                       ventilating brick or steel plate laid in the side
   c. Demolition by Crown Charges. Crown                       wall of the arch. Charges placed in the haunch
charges are more easily and quickly placed than                on the left side will drop out that portion of the
haunch charges; but their effectiveness is sub-                arch between lines C and D as shown in figure
s~antially less, particularly on an' arch with a               135. Charges in both haunches will drop out
fIse that is large in comparison with the span.                that portion of the arch between lines C and E.
Crown charges are more effective on the flatter                The breaching charges must be placed on the
arches because the flatter shape permits a                     arch ring either in holes on the top or supported
broken portion of the arch to drop out of the                  on the under side.
b 'dge, Breaching charges are placed as shown
                                                               117. Open Spandrel Arch Bridges
In  figure 134.                                                   An open spandrel arch consists of a pair of
. d. Demolition by Haunch Charges. Breach-
I~g charges may be placed at the haunches                      arch ribs that support columns or bents which
 (Just ahead of the abutment) as shown in fig-                 in turn support the roadway. The number of
ure 135 and the traffic maintained until they                  arch ribs may vary, and on rare occnsions the
are fired. If the bridges have demolition                      spandrel bents may be placed on a full barrel
vaults or chambers built into the haunches, the                                                               133

AGO   7258A
              Figure   128.     Placement   of charge   to cut diagonal   and upper   and lower chords.

                       Figure    129.   Placement   of charges   to cut trusses   into segments.
arch similar to that which supports the filler
                                                                 feet in length to 3 feet for spans of 200 feet
material of the filled spandrel arch. The open
 or more. The arch thickness at the spring line
spandrel arch bridge (fig. 136) may be con-
                                                                 is ordinarily about twice the thickness at the
structed of reinforced concrete, steel, timber,
                                                                 crown. In long spans, the ribs may be hollow.
or any combination of those materials.
                                                                 The f.oor slab ,is usually close to the crown,
   a. Demolition of Concrete Open Spandrel
                                                                 permitting packing of charges against the rib
A rch. The ribs of a concrete open spandrel
                                                                 at this point. Here again, the same difficulties
arch bridge (fig. 136) are about 5 feet wide.
                                                                 are found in reaching the working points at
The thickness of the arch rib at the crown
                                                                 the crown as in T-beam (para 112) or in
varies from about 1 foot for spans of. 50 to 60
                ,                                                stringer bridges (para 110). Since for struc-
                                                                                                          AGO 7258A
                                                    continuous          ,pan   truss.
                 Figure   130.   Demo l'tion . 01 a


                                             cantilever   tru   8B   wt'th ,uspen ded .pan.
                              l'tion    0f
              Figure 131. Demo 1

AGO   7258A
                                                                                                 CUT     TRUSS   HERE

                  Figure   132.   Demolition      of cantilever    truss   without   suspended   span.


                                         Figure     133.   Arch    components.

tural reasons, the haunch over the abutment                       a relatively short distance.  This may make
is most likely to be heavy, effective destruction                 the damaged bridge an excellent support for
of the arch itself by means of light crown                        building a new temporary bridge.     Therefore
charges may leave a substantial pier at roadway                   to prevent utilization of such a span, one
level in an undamaged condition.       This type                  charge is placed at the haunch and another at
of structure is usually built in one massive unit                 the crown. The uncut half-span will then also
 rather than in lighter separate component                        fall if the total span exceeds 50 or 60 feet.
parts and is very tough. Also, cutting the                        The charge at the haunch is computed for
span at each end , may drop the whole span only                   placement at either the ring or the pillar over
136                                                                                                                     AGO 7258A
                 Figure 13.. Breaching by crown charge. on filled .pandrel arch bridge.
                                                      jor bridge distinguished by two characteristics:
~e support, whichever has the greater radius.         the roadway is carried by a flexible .member,
  or sho.rt single arch spans, destroy the entire     usually a wire cable, and the spans are long
Span wIth breaching charges laid behind the            (fig. 138).
abutments or behind the haunches.                        a. Components.
   b. Demolition of Steel Arch Span. Steel                  (1) Cables. Cables of suspension bridgE's
arches are of four general types: continuous                     are usually two stE'el multi-wire mem-
arches « 1) fig. 137), one-hinged arches (2),                    bers that pass over the tops of towers
two-hinged arches (?), and three-hinged arches                   to anchorages on each bank. The
 (4) . One-hinged arches are hinged in the mid-                   cables are the load-carrying members.
                                                                  (The "Golden Gate" bridge has
dIe; two-hinged arches at both ends. and three-
hinged arches, at both' ends and in the middle.                   127,000 miles of cable wire.)
Continuous arches and one-hinged arches are                 (2) Towers. Towers of a suspension
destroyed by placing charges at both ends of the                  bridge support the cables or load-
sp an Just far enough from the abutment to
        .                                                         carrying members. They may be made
a~low the arch to fall. Two-hinged and three-                     of steel, concrete, masonry, or a com-
hInged arches need only one charge apiece for                     bination of these materials.
 destruction.    This should be placed at the cen-           (3) Trusses or girders. The trusses or
 ter of the span.         .                                      .girders of a suspension bridge do not
                                                                  support the load directly. They pro-
 118. Suspension    Span Bridges                                  vide stiffening only .
   The suspension   span bridge is usually a ma-                                                     137

.<\.GO 7258A
      Figure   135.

      Figure   136.       ' <%W~
                      Demolition of reinforced   con crete                      h bridge.
                                                             open 8p andrel arc

138                                                                                         AGO 721i8A
                                        Q)    CONTINUOUS      ARCH

                                         @    ONE-HINGED      ARCH

                                         GD   TWO-HINGED       ARCH

                                         0)   THREE-HINGED       ARCH

                              Figure   131.   Demolition   0/ steel arch bridges.
                                                                        for positive cutting with explosives.
      (4) Anchorage.   The usual anchorage is                           The most economical method of de-
          merely the setting of the splayed end                         struction is either by dropping the
          of the cable in a rock or a concrete                          span leading onto the bridge or drop-
          mass. This may be large-sometimes                             ping a section of the roadway by
          as much as 1000 cubic feet in size.                           cutting the suspenders of the main
                                                                        or load-bearing cables. The length
  b. Destruction.                                                       of this section should be determined
     (1) Major structures.     The towers and
         anchorages    of a major suspension                            by an analysis of what capabilities
                                                                        the enemy has for repair in the time
         bridge are usually too massive to be
          destroyed, and the cables are too thick                                                         139

AGO   7258A
                                                        way of metal or wood supported by floats. or
                                                           a. Pneumatic Floats.       Pneumatic floats con-
                                                        sist of rubberized fabric made into airtight
                                                        compartments and inflated with air.
                                                               (1 ) Hasty method of destruction.       The
                                                                    anchor cables and bridle lines may be
                                                                    cut with axes and the steel cable, by
                                                               (2) Deliberate method of destruction. The
                                                                    floats may be punctured by small armS
        Figure   138. Suspension   .span bridge.                    or machinegun fire. This requires a
                                                                    considerable volume of fire because of
          he is expected to retain the site, par-                   the large number of watertight com-
          ticularly the erection of a prefabri-                     partments in each float. Detonating
          cated bridge.      It may also be feasible                cord stretched snugly across the sur-
          where there are reinforced concrete                       face of inflated ponton compartments
          towers to breach off the concrete and                     will make a clean cut through the ma-
          cut the steel.                                            terial.  One strand will suffice to cut
      (2) Minor structures.        The two vulner-                  most fabrics; two may be required for
          able points of a minor suspension                         heavier material. Also one turn of de-
          bridge are the tower and the cables.                      tonating    cord around an' inflation
      (3) Towers.       Charges may be placed on                    valve cuts it off at the neck or does
          the towers slightly above the level of                    other damage.      Lines placed around
          the roadway.       A section should be cut                valves should not be main lines but
          out of each part of each tower.          A                branch lines run off from the main
           charge is placed on each post to force                   line, as the blast wave may fail to
           the ends of the cutout section to move                   continue past the sharp turn.
           in opposite directions twisting the              b. Rigid Pontons.      Rigid pontons are made
           tower. This will prevent the ends of         of various materials such as wood, plastic, or
           a single cut from remaining in con-           metal. Most of these are open but occasionally
          tact. Demolition chambers, provided           they are decked over.
           in some of the newer bridges, make                   (1) Hasty method of destruction.      A lh-
           blasting easier, quicker, and more ef-                   pound charge of explosive is placed
           fective.                                                  on the upstream end of the. bottom of
      (4) Cables. Charges should be placed on                       each ponton and detonated simultan-
           the cables as close as possible to firm                  eously. If the current is rapid, an-
           support such as at the top of the tower                  other method is to cut the anchor
           or at an anchorage. Extreme care                          cables so that the brIdge will be car-
           should be taken to extend the charges                     ried downstream.               .
            not more than one-half the distance                 (2) Deliberate method of destruction. The
           around the circumference of the cable.                    bridge is severed into rafts and half-
            These charges are bulky, exposed, and                    pound charges of explosives are placed
           difficult to place; and the cables are                    at each end of each ponton and deto-
            difficult to cut because of the air space                nated simultaneously.
            between the individual wires. Shaped            c. Treadways .. Charges to destroy the tread-
            charges, however, with their directed        way of any metal treadway type of floating
            force effect, may be used to advantage.      bridge may be calculated by means of the steel-
                                                         cutting formula.       The placement and amount
119. Floating Bridges
                                                         of the charges to be used depends on the type
  Floating bridge~ consist of a continuous road-         of bridge to be destroyed. In general, if charges
140                                                                                               AGO 7258A
                                                              chords at the story junction line.
are set to sever the roadway completely at                (2) For further destruction, charges are
every other joint in the treadway, the bridge                 placed on the transoms and the string~
will be damaged beyond use.                                      ers.
                                                          b. Bridges in Storage or Stockpile. Destruc-
120. Bailey Bridges                                   tion of bridges in storage must be ~mchthat the
   A I-pound charge placed between the chan-          enemy cannot use any of them as a unit or any
nels of the upper and lower chords will destroy       parts for normal or improvised construction.
t~e panels.    A lh-pound charge will cut the         This requires that one essential component, not
dIagonals and a I-pound charge the sway               easily replaced or improvised, be destroyed so
bracing (fig. 139).                   '               that the bridges at a particular stockpile can-
   a. Bridge in Place.                                 not be used. In this way it will also be im-
      (1) The bridge is severed into parts by          possible for the enemy to obtain replacements
          cutting panels on each side, including       for other sectors. The component that fulfills
          the sway braces.     The line of cut is      all of these conditions is the panel. To make
          staggered through the panels; other-         the panel useless, the female lug in the lower
           wise the top chords may j am and pre-       tension cord is removed or distorted.        All
          vent the bridge from dropping.       In      panel3 should be destroyed before other com-
           double-story or triple-story  bridges,     ponents are destroyed.
           the charges are increased on the

                       Section IV. DAMAGING TRANSPORTATION LINES
                                                               vehicle supplied with explosives, non-
121. Highways                                                  electric blasting caps, time fuse, fuse
   ~isruption of enemy transportation      lines is             lighters, and filled sandbags.   Several
an Important demolition objective. The extent                   soldiers ride the vehicle, prime 1-
 . emo l.t'1 lOn, however, depends upon the analy-
                                                                pound charges, and hand them, to-
of d
SI.S of the system and the mission. By the                      gether with sandbags, to men walking
destruction of the road net, the attacking forces               immediately behind the vehicle. These
~re halted or delayed, the movement of supplies                  men place the charges against the rail
~s prevented, and frequently new construction                   on alternate connections of both tracks
                                                                for a distance of about 500 feet, and
IS reqUIre d before
          •              the enemy can advance.
                                                                then tamp them well with sandbags.
This may be accomplished by the demolition of
                                                                 Tamping is not required to break the
bridges, ?y blowing road craters, by placing
                                                                 rail, but will destroy a longer length
wrecked Items of equipment and debris in cuts
                                                                 of rail. Other men follow about 250
and defiles, and by the construction of abatis
                                                                 yards behind the vehicle to light the
and roadblocks.                                                  fuses. This method requires approxi-
 122. Railroads                                                  mately 20 pounds of explosive per 500-
                                                                 foot length of single track line. It
   a. Tracks.                                                    should be repeated at approximately
      (1) If possible, the destruction of rail-
          roads with explosives should be done                   I1h-mi1e intervals.   Such procedure is
          at vulnerable points. These are curves,                particularly   advantageous when the
          switches, frogs, and crossovers, which                 supply of explosives is limited or when
          may be destroyed with a small amount                   time or other factors prohibit com-
          of explosive.   This is called the "spot"              plete destruction of a line. It causes
          method.    Placement     of charges is               . a greater delay in repair than a con-
                                                                 centrated destruction of short lengths
          shown in figure 140.
                                                                 of track. If time, explosives and other
      (2) A length of single track may be de-
                                                                 conditions permit, however, complete
          stroyed rapidly by a detail of soldiers
          with a push car, lA-ton truck, or other                                                   141

 AGO   7258A
                                                                   section of track, fastening a heavY
                                                                   chain or cable to it, and pulling it up
                                                                   by a locomotive.    Also, a large hook
                                                                   towed by a locomotive is useful to tear
                                                                   up ties and rails.  Whenever possible,
                                                                   ties loosened from the rails should be
                                                                   piled and burned.
                                                             b. Roadbeds. Roadbeds are damaged by the
                                                          methods used in making road craters and anti~
                                                          tank ditches.
                                                          123. Tunnels
  ! LB     BETWEEN                                           Railway and highway tunnels located on
                                                          major routes to strategic industrial or military
                                                          areas are vulnerable to demolition and there~
                                                          fore desirable     targets.   Tunnel   demolition,
                                                          however, with hastily placed conventional eX~
                                                          plosives is impossible unless huge quantities
                                                          are used. But when demolition chambers exist
                                                          or time, men, and equipment are available, con~
                                                          siderable damage to tunnels can be accom~
                                                          plished with reasonable amounts of explosive.
                                                             a. Princ'ipal Factors in Tunnel Demolitions.
                                                          The most critical factor in tunnel demolition
                                                          is the tightness of the lining against solid rock.
                                                          The actual thickness and strength of the lining
                                                          are of secondary importance.       The degree of
                                                          contact of the walls with surrounding         rock
                                                          influences the amount of blast energy trans~
                                                          mitted to the rock or retained in the concrete
                                                          and the consequent movement of broken frag~
                                                          ments, which may permit their being dislodged
                                                          and dropped into the tunnel.
                                                             b.Hasty Demolitions.      The hasty demolition
                                                          of tunnels with reasonable amounts of conven~
                                                          tional high explosives is ineffective.   No hasty
                                                          method has yet been devised that will' cause
                                                          extensive damage.       The enemy may be tem~
                                                          porarily deprived of the use' of a tunnel by
         Figure   139.   Demolition   0/ Bailey bridge.   breaking and dislodging portions of the lining
                                                          with normal breaching charges placed at a
          destruction of long lengths of track
                                                          number of points and by creating slides at the
          will provide maximum delay.
                                                          tunnel portals by placing cratering charges in
      (3) Tracks may be made unserviceable                the slope above them. Nuclear,devices of prop~
          without the use of explosives by tear-          er size advantageously placed, will effectively
          ing up sections of the track, especially        demolish a tunnel.
          along cuts, fills, or embankments,
                                                             c. Deliberate Demolitions.     Deliberate tun~
          where the use of reconstruction equip-          nel demolitions will produce satisfactory results
          ment is restricted and work areas are           when explosive charges are detonated in pre~
          limited. This may be done by remov-             pared chambers in the material adjacent to the
          ing fighplates from both ends of a              inner face of the tunnel, whether it is lined or
142                                                                                                AGO 7258A
                       Figure   140.     Demolition   of railroad   switches,   frogs, and   Crossovers.   ,

 not..    Excessive charges            are   not required.                      foot burden. Charges should be placed
 MaxImum damage desired in any tunnel is that                                   on 30-foot centers.                 .
 of obstructing it with broken rock. Secondary                            (3) Stemming.      Stemming, the material
 damage by fire may also occur. Ca,ving, which                                with which a borehole or charge cham-
 may result from structural damage to the tun-                                ber is filled or tamped (usually earth-
 nel arch, cannot be predicted. To obtain maxi-                               filled sandbags) • is necessary. It
 mum damage to tunnels, the methods outlined                                  should extend from the last charge in
 below are adequate.                                                          the T-type chamber to the chamber
       (1) Charge chambers. Tunnel charge                                     entrance. Stemming is not necessary,
           chambers should be so constructed                                  however, between charges within the
               that each chamber parallels the long                          chamber.
             axis of the tunnel at or above the                       d. Deliberate Demolition of Tmmels With
             spring line. The T-design tunnel                       Prepared Charge Chambers. Some tunnels
             charge chamber is an efficient means                   have chambers or holes in the roof for the
             of inflicting serious damage. The                      purpose of demolishing them at some future
             chambers may be constructed opposite                   time. Their presence is usually indicated by
             each other at staggered intervals on                   the open brick ventilators placed over them. If
             opposite sides, or all on one side of the              no ventilators are present, these chambers may
             tunnel. The maximum burden, which                      be located by striking the roof of the tunnel
             is the distance from the charge to the                 with some heavy metallic object, which usually
             inside rock wall, should be 15 feet. The               produces a hollow sound. Explosives, com-
             tunnel charge chamber should be no                     pacted as tightly as possible, are placed in the
             larger than necessary for convenience                  chambers, which are then closed and sealed
             of construction and loading and no                     except for the place where the fuze or firing
              smaller than 3 feet wide by 41/2 feet                 wire passes through. Sandbag stemming is
              high. Charge chambers should be con-                  recommended in all charge chambers in tim-
              structed' far enough inside the tunnel                bered tunnels, as the sandbags increase the
              portal to insure confinement of the                   possibility that the timbers may Ignite when
              charge. The minimum of side hill or                   the charge is detonated.
              outside burden should be 30 feet.                     124. Water Transportation Systems
         (2) Charges. Seven hundred and fifty                         The extent of demolition depends largely up-
              pounds of high explosive is an effec-                 on the mission, materials available, and an
              tive minimum charge for single place-                 analysis of the system as to. how critical, ac-
              ment within a T-type chamber of 15-                   cessible, repairable, and vulnerable it may be.

  AGO 7258A
   a. Vessels, Piers, and lVarehouses.    Vessels      the preparation         for an organized withdraw'al
can seldom be destroyed efficiently by landbased       when seizure by the enemy is imminent.
troops, unless they are tied up at docks, piers,            a. Plans for Demolition.                      .
and warehouses, however, are excellent demoli-                 (1) The methods of destroying any airfield
tion targets, especially for the use of fire.                        depend on the materials at hand, the
   b. Channel.s. The most expeditious way to                         type of installation to be destroyed,
block a channel is to sink a ship or a loaded                        and the time and equipment available
barge at a point that cannot be bypassed.                            to complete the job. Aircraft           and
Channels with retaining walls may be blocked              •          equipment may be destroyed instantly
effectively by detonating breaching charges be-                      by directing      weapons fire against
hind the retaining walls.
                                                                     them. Whenever possible, bombs and
   c. Dams. Since a prohibitive amount of ex-                        ammunition should be used as explo-
plosive is generally required 'to destroy an en-                     sive charges (app C). Gasoline and
tire dam structure,     the best and quickest                         other fuels (POL products) may be
method is to destroy the machinery and the                           used to aid in the destruction, by fire,
equipment.    If the purpose of the demolition                       of vehicles, equipment, and buildings.
is to release the water in the dam, all that is                (2) When time permits, a detailed plan
required is to destroy the gates on the crest of                     for demolition of the airfield should
the dam, the penstocks or tunnels used to by-                        be prepared before any charges are
pass the dam or to carry water to hydroelectric                       placed. This should include-
plants, or the valves or gates used to control                    (a) Location of charges.
the flow in the penstocks or tunnels.    In dams,                 (b) Type of explosives.
partly or wholly constructed of earth fill, it may                (c) Size of each charge.
be possible to ditch or crater down below the                     (d) Priority      in preparation   and place-
existing waterline and thus allow the water                              ment of each charge.
ib;elf to further erode and destroy the dam.                      (e) Total amount of itemized explosives
Nuclear devices may also be used to advantage.                           and other materials needed to effect
    d. Canals. In most cases, a canal may be                             demolitions included in the plan.
made useless by destroying the lock gates and                      (f) Assignment of personnel or groups
the operating mechanism that controls them.                              to prepare specific charges.
This mechanism, which includes the electrical               b. Priorities for DemOlition.          It is seldom
equipment and perhaps pumps, is the easier to          possible to destroy an airfield completely be-
dm;troy and should therefore be attacked first.        cause of the great amount of explosives and
If time permits, the gates themselves may be           time required.          Thus it is necessary to deter-
destroyed.    The lock walls and canal walls may       mine what specific demolition is to be done and
be destroyed by breaching charges or cratering         in what order specific operations are to be
charg-es placed behind them.                           accomplished.          Airfield demolition plans should
125. Airfields                                         be very flexible, particularly in regard to priori-
   Airfields may be destroyed by ADM. They              ties. The order of priority sho'uld vary accord-
may be rendered unusable by cratering run-             ing to the tactical situation.            The following
ways or placing objects on surfaces to prevent          list suggests an order of priority for airfield
use by aircraft.      The destruction of POL and        demolition, which may be modified to suit the
munitions stocks and of repair and communica_           tactical situation.
tions facilities is also effective. Rooters, plows,             (1) Runways        and taxiways      and other
and bulldozers can ditch runways that are not                         landing areas.
constructed of concrete.        Friendly operational            (2) Routes of communication.
and nonoperational airfields should be destroyed                (3) Construction equipment.
only in areas where the resulting wreckage will                 (4) Technical buildings.
provide the maximum impediment to enemy                         (5) Supplies of gasoline, oil, and bombs.
movement and operations.          They should, how-             (6) Motor vehicles and unserviceable air-
ever, be made ready for demolition only during                        craft.
                                                                (7) Housing facilities.
                                                                                                      AGO 72fiRA
                                                           placed on the instrument panel to prevent
      c. Runways and Taxiways.          Runways and        salvage. The engines of jet-propelled aircraft
 taxiways have first priority in a demolition              should be destroyed by detonating charges on
  ~lan because the destruction of landing surfaces         essential parts, such as the compressor, air
  IS the most important single item. ,\Vhenever            intake, or the exhaust turbine.   Radio equip-
 possible, demolition of an airfield should be             ment, bombsights, radar, and tires should be
  considered during construction by the placing            removed or destroyed.
  of large conduits in all fills This requires
  • 1 tIe extra work and provides . means of plac-
                                     a                     126. Pipelines
                                                                                            of a pipeline
  Ing. explosives under the runway.         Standard         The most vulnerable points
                                                                                            and pumping
  delIberate and hasty craters may be useful in            system are the storage tanks
  the demolition of runways            and taxiways.        stations.
  Shaped charges may be used to breach thick                   a. Storage Tanks. Storage tanks filled with
, conc.rete pavement when speed is essential. The         . fuel may be destroyed most effectively by \
  placIng of individual cratering charges diagon-           burning with incendiary grenades or the burst.
  a~IY down the runways or taxiways, or in a                of .50-caliber incendiary ammunition.   Empty
  zIgz~g line running diagonally back and forth,            tanks may be destroyed by detonating charges
  p~ovldes more complete destruction.           '\Vhen
                                                           against the base.
  Plerc~d steel plank or other type of landing
  mat IS used on an airfield, substantial damage              b. Pumping Stations.    Booster pumping sta-
  may. be done by attaching a large hook to                tions on cross-country pipelines, being very
   se.ctlOns of the mat and pulling it out of place        vulnerable, should be destroyed.      Gravel or
  wIth ~ tractor.      This should be followed by          other solid objects introduced into the pipeline
  cratenng.      A hasty, satisfactory obstacle may        while the pumps are running will damage the
  be produced by the use of 40-pound cratering             moving parts, although not to the degree possi-
   charges spaced every 15 feet across the runway          ble with explosives. If time permits, the
                                                           pumping station should be burned after the
   and buried 4 feet under the ground.
                                                           equipment has been destroyed by explosives.
  . d. Turf Surfaces and Pavements.    Bitumin-
                                                              c. Pipe. The pipe used in pipelines is de-
 ous surface treatments or thin concrete pave-
                                                           stroyed only during scorched earth operations
 ments can be destroyed by bulldozers, graders,
                                                           because of the great amount of effort necessary
 and rooters. Turf airstrips can be destroyed
                                                           for effective damage. Junctions, valves, and
 by plowing or cratering.                                  bends are the most suitable points, particularly
    e. Aircraft.  Unserviceable aircraft should            when the line is buried. Another method is to
 be destroyed by the detonation of 4 pounds of             close all valves on the line; the expansion that
 TNT placed on each crankshaft between the                 occurs, even in subzero weather, will break it.
 propeller and the engine and 1 pound of TNT

                       Section   V.    DAMAGING          COMMUNICATION        SYSTEMS

                                                           pole lines are not satisfactory targets as they
 127. Telephone and Telegraph Lines
                                                           are strung over long distances and can be de-
    Although damage to an enemy telephone
                                                           stroyed only in spots. They may be made tem-
 system or telegraph system may never be exten-
                                                           porarily useless by cutting or grounding the
 sive, it does have a great delaying effect. Tele-
                                                           wires or by cutting the poles with small ex-
 ~hone     and    telegraph   switchboards    and
 Instruments    are the best points of attack.             ternal timber-cutting charges and then burn-
 Generally I-pound charges placed on the cables            ing. The wire should be cut into short lengths
 are adequate to sever them. Also dial systems              to prevent further use.
 may be damaged by smoke from burning oil.                                                              145

  AGO   7258A
128.       Radio Installations                             high voltage tr~nsmission line through which
   Radio provides rapid communication between              the installation received its power.   Equipment
far distant points that would otherwise be with-           and standby power units may be destroyed by
out communication.      Antenna towers, usually            mechanical means or by demolition charges.
constructed of steel and braced with guy wires,            Transformers     also are very vulnerable.   They
are the most accessible part of any radio in-              will burn themselves up if a hole is blasted in
stallation.  They are destroyed by cutting the             the side or bottom and the oil let out, provided
 guy wires and by placing cutting charges                  they do not have automatic thermo cutoff
against the base. The towers should be top-                switches.
pled over the transmitter station or across the

                  Section VI.       DESTRUCTION       OF BUILDINGS     AND     INSTALLATIONS
129.       Buildings                                       should be studied so that the amount of damage
    Buildings may be destroyed by explosive or             will be adequate but not exceed tactical de-
 other methods.     The methods used and the               mands. They may be destroyed by cutting the
extent of demolition usually depend on the time            windings of generators and motors, by placing
 available.                                                and detonating a 2-pound charge inside the
    a. Masonry or Concrete Buildings. Masonry              casings, or by pouring gasoline on the genera-
 or concrete buildings may be destroyed by                 tors and lighting them. Generators also may be
 breaching charges placed on the inside and at             "shorted" out by the use of metal powder or
 the base of the exterior walls.                           shavings. The shafts of motors and generators
    b. Wood or Thin-Walled Buildings. Wooden               are broken. Damage can also be done by re-
 frame buildings may readily be destroyed by               moving or contaminating      the lubricating   oil
 fire. Another method is to close all doors and            with metal filings or aluminum powder and
 windows and explode on the ground floor a                 then running the machinery.     Boilers are burst
concentrated charge (dust initiator) equal to              with a cutting charge.     All buildings, trans-
 1/~ pound to 1 pound of explosive per cubic               mission towers, penstocks, and turbines         of
yard of volume (app F). Such buildings may                 hydroelectric plants may be destroyed.
be dismantled, however, if time permits.                   131.   Water   Supply
    c. Steel Framed Buildings. Stink bombs and                 The pumping station, filtration plant, and
other malodorous devices and contaminants                   reservoirs of a water supply system are usually
may be all that is required to damage the in-              the points most accessible to attack. Storage
terior furnishings     or equipment.       Another         tanks are demolished by charges calculated on
method-to     expose the interior to extreme heat,         the basis of 1 pound of explosive per lOO-cubic
1000 F for 10 minutes-will        cause failure of         foot capacity. The charge is detonated inside
the structural steel members. Buildings with               the tank when it is full of water. The water
steel frames may also be destroyed by first                acts as a tamping material.       Shaped charges
breaching the concrete or masonry where neces-             are also useful in this capacity.    The standoff,
sary to expose the vital steel members and then            however, should be cut dow~ considerably.
cutting them with explosive charges.                       'VeIls sunk in soft soils are damaged beyond
    d. Concrete Beam, Curtain ~Vall Buildings.             repair by charges that cut the lining.        WellS
Concrete beam curtain wall buildings, con-                 in rock and hard soils, having little or no lining,
structed in such a way that the load is carried            are demolished by exploding large breaching
by reinforced concrete beams and columns, are              charges 6 to 12 feet from the edge of the well
destroyed by placing breaching charges inside              and deep enough to secure good tamping.           If
the buildings at the base of the exterior wall             time does not permit such preparation, a large
and at the base of all intermediate columns on             charge is exploded halfway down against the
the ground floor.                                          side.
130.       Electric Power Plants                           132.   Petroleum,   Oil, and Lubricating
  Before       destructi,on,   electric   power   plants
                                                             POL refineries    are readily   demolished,   hav-
146                                                                                                   AGO 72r;8A
                                                     such installations should be planned and exe-
ing such extremely vulnerable points as crack-       cuted only by persons familiar with their de-
ing towers, steam plants, cooling towers, and        sign and -construction    or after extensive
POL stock. These are easily damaged by ex-           investigation.
plosive charges and fire. The demolition of

                                                     134. Planning
133. Introduction                                       Standing operating procedures for all units
   a. Authority for Destruction.   The destruc-      should contain a plan for the destruction of all
tion of friendly materials is a command deci-        equipment and supplies except medical sup-
sion, implemented only on authority of the           plies, which are left intact for enemy capture.
division or higher commander.        Equipment       Such a plan will insure that the maximum and
and supplies that cannot be evacuated and may,       most effective damage is done to materiel and
therefore, be captured by the enemy are de-          will deny the use of friendly equipment to the
stroyed or made unserviceable, except for medi-      enemy. It should outline the required extent
cal materials and stores, which are not to be        of demolition and include priorities of demoli-
intentionally   destroyed (DA Pam 27-1 and           tion and methods of destruction for all items
FM 8-10).                                            issued to the unit. If explosives are .to be
                                                     used, the amounts required should be indicated.
   b. Destruction    Areas.    'Vhenever possible,
                                                     The plan must be flexible enough in its de-
mobile equipment is demolished in places where
                                                     signation of time, equipment, and personnel to
it Inost effectively impedes the advance of the
                                                     meet any situation.    In order to make canni-
enemy. Examples of such places are-
                                                     balization by the enemy impossible, each equip-
      (1) Approaches to bridges (fills).
                                                     ment operator must be familiar with the
      (2) Airfield landing strips.                   priority sequence in which essential parts, in-
      (3) Cuts, fills, or hills on roadS.            cluding extra repair parts, are to be destroyed.
      (4) Sharp bends of roads.                      He must also be familiar with the sequence
      (5) Roads leading through densely wooded       to be followed for total destruction.
      (6) Narrow streets in thickly populated or
                                                     135. Methods of Destroying Material
                                                        The following methods of destroying ma-
          built-up areas.
                                                     terial may be used either singly or in combina-
   c. Priority of Operations.   Destruction must     tion. The actual method or methods used in a
be as complete as the available time, equip-         given situation depend on the time, personnel,
ment, and personnel will permit.      If all parts   and means available.
of the equipment cannot be completely de-               a. Explosives.     All military exploRives are
stroyed, the most important ones should be           effective in destroying equipment.
damaged.      Special attention must be given to        b. J,I echanical J,I ea11.'f. Material may be de-
those parts that are not easy to duplicate or        stroyed by mechanical means. Sledge ham-
rebuild.    Particular care must be taken that       mers, crowbars, picks, axes, and any other
the same components are destroyed on each            ava.iIable heavy tools are used to smash or
piece of equipment; otherwise the enemy may          damage whatever is to be destroyed.
assemble a complete unit with parts taken from          c. iI'eapons Fire. Hand grenades,            rifle
several partly destroyed units (cannibaliza-         grenades, antitank rockets, machinegun fire,
tion) .                                              and rifle fire are a valuable means of deRtroying
   d. Precautions.   When material is destroyed      materiel.
by explosives or by weapons fire, flying frag-          d. Thermite Grenades. Flammable mate-
ments and ricocheting bullets create a hazard.       rial and equipment may be destroyed or made
Thus demolition must be accomplished in an           unserviceable by heat generated by the thermite
area free of friendly troop concentrations.                                                           147

AGO   7258A
grenade.     The material should be soaked witJ:1         . Vital parts of entire items may be hidden by
fuel before burning.                                        throwing them into a lake, stream, or other
   e. Fire. Rags, clothing, or canvas should be             body of water (f above).
packed under and around the materiel to be                     i. Booby trapping.   Booby traps are placed in
destroyed.     It should then be soaked with gaso-          debris after destruction is completed. if time
line, oil, or diesel fuel. Damage from fire may             permits.    See FM 5-31 for the techniques.
not always be as severe as expected.           Engine
                                                          136. Destruction of Combat Equipment
or transmission parts heated to less than a dull
red heat are not seriously damaged provided                  There are various publications on the proper
they are lubricated immediately after the fire            methods of destroying military combat equip-
to prevent corrosion.      Electrical equipment, in-      ment. The FM 23-series is concerned with the
cluding motor or generator armature windings              destruction of small arms such as rifles, pistols,
and other wiring, is effectively destroyed by             mortars, and ammunition;       and the FM 17-
burning.      All parts made from low-melting-            series, with the destruction of armored vehicles
point metal may be almost completely destroyed            and their weapons.
by fire.                                   ~
              137. Training
    f. Water. The damage resulting'from sub-
merging equipment in water is not generally                   Training does not involve the actual demoli-
very severe, but the method is sometimes rather            tion of any mat~riel but the simulated break-
quickly and easily accomplished.           Total sub-      ing of vital parts, the placing of dummy
mersion also provides concealment of equip-                charges, and the selection of sites suitable for
 ment (h below).                                           the destruction of equipment in order to block
    g. Abuse.     Much damage can be done to               communication routes.     Drivers and operators
 equipment, particularly to engines, by deliber-           should be made familiar with each step in the
 ate improper operation.        Such abusive' treat-       appropriate method for the destruction of their
 ment may proceed even after abandonment, if               e~uipment and supplies.    It should be empha-
 hasty action becomes necessary, by leaving the            SIzed that in planning destruction operations,
 equipment in an improper operating condition.             the following methods should be considered in
    h. Concealment.      Easily     accessible    vital    the order given:
 component parts of equipment may be removed                 a. Mechanical damage to vital parts.
 and 'scattered through dense foilage, thus pre-             b. Use of explosives.
 venting or at least delaying use by the enemy.              c. Use of weapons fire, fire, and water.

 148                                                                                                 AGO 7258A
                                                        CHAPTER 5
                                  SAFE HANDLING, TRANSPORTATION, AND
                                         STORAGE OF EXPLOSIVES

                                     Section I.   GENERAL SAFETY PRECAUTIONS
138. Safety Rules and Responsibility                                  responsible for the supervision of all phases of
                                                                      the demolition mission.
   a. Compliance. Safety rules regarding ex-
plosives, caps, and demolition equipment will be
                                                                      139. Safe Distance Formula
followed strictly during training.    In combat,
however, some must of necessity be altered so                            Distances at which persons in the open are
that unit missions may be accomplished. In all                        safe from missile hazards from bare charges
other situations they will be observed to the                         placed on or in the ground are given in table
fullest extent permitted by time, materials                           XIV. The formula for computing safe dis-
available, and requirements of the mission ..                         tances from explosives so placed is-Safe    dis-
Also, post regulations and local and units SOP's                      tance in feet=300 vpounds of explosives. (For
will be observed.                                                     quarrying    the safe distance in feet = 350
   b. Responsibility. The responsibility of, the                      vpounds of explosives). The minimum safe
preparation, placement, or firing of charges                          distance for soldiers in a missile-proof shelter
must not be divided. One individual should be                         is 300 feet (AR 38~63).

                        Table XIV.     Minimum safe distances from explosives for persons in the open

                                                                                                                   Safe distance
                                                  Safe distance               Pounds   of   explosive
          Pounds   of explosive                                                                                        in feet
                                                      in feet

1-27                                                    900             150   ---~---------------------------            1,678
   28                                                   909             175   -------------------------------            1,754
   29                                                   921             200   --------------------~------~---            1,825
   30                                                   930             225   -------------------~~----------            1,890
  32                                                    951             250   -------------------------------            1,951
  34                                                    969             275   -----~-----------~-------------            2,008
  36                                                    990             300   -------------------------------            2,063
  38                                                  1,008             325   ----------------- --------------           2,114
  40                                                  1,020             350   ------------ -------------------           2,163
  42                                                  1,041             375   -------------------------------            2,210
  44                                                  1,050             400   ----------------- --------------           2,256
  46                                                  1',074            425          ----------- --------------          2,299
  48                                                  1,080             450   ------------------------                   2,341
  50                                                  1,104             475   ----~--------------------------            2,381
  55                                                  1,141             500   -------------------------------            2,420'
  60                                                  1,170             525   ----------------- --------------           2,458
  65                                                  1,200             550   -------------------------------            2,495
  70                                                  1,230             575   -------------------------------            2,530
  75                                                  1,260             600   ----------------- --------------           2,565
  80                                                  1,290             625   --------------------- ----------           2,599
  85     ------~--------~-----------------            1,317             650       ._------------------- --------         2,632
  90                                                  1,344             675   -------------------------------            2,664
  95                                                  1,368             700   --------------- ----------------           2,695
 100                                                  1,392             725   -------------------------------            2,725
 125                                                  1,500             750   -------------- -----------------
AGO     7258A
                                                                        ~or safety rules cause premature explosions,
                                                        Safe distance
 Pounds    of explosive
                                                            in feet     misfires, and in many cases serious accidents.
                                                                        Issued explosives and auxiliary items are
775      ---------------------------------                   2,785      packed in moisture-resistant containers and
800      ---------------------------------                   2,814      proper packing boxes to withstand field condi-
825      ---------------------------------
850      ------------------------------_._-                  2,842      tions of transportation and storage. Containers
875      ---------------------------------                 , 2,896
                                                                        and boxes must never be handled roughly; they
900      ---------------------------------                   2,923
                                                                        must never be broken, cracked, or dented. Some
925      ---------------------------------                   2,949      special items, if distorted, lose part of their
950      ---------------------------------                   2,975      effectiveness. Damaged packing boxes and con-
1000                                                         3,000      tainers must be repaired immediately; all de-
 Note.   Chart   is based on formula:                                   faced parts of marking must be transferred to
                                        d    300 yP.                    new parts of the boxes. Broken airtight con-
                                        d   safe distance. in feet
                                        p   pounds of explosive
                                                                         tainers, such as those containing chemical
140. Package Care and Repair                                            mines, should be destroyed.
   Carelessness, rough handling, and disregard
                   Section II. TRANSPORTATION,                           STORAGE, AND DISPOSAL
141. Transportation                                                              of explosives shall be in charge of, and
   a. Safety Policy. Local transportation of ex-                                 operated by, a person who is mature-
plosives for immediate use is directed by AR                                     minded, physically fit, careful, reliable,
385-63. The Department of the Army clearly                                       able to read and write the English
defines the safety responsibilities of transpor-                                 language, and not addicted to the use.
tation officers at their installations. Local safety                             of intoxicants or narcotics. He should
SOP's are provided to insure that all persons                                    be aware of the destructive effects of
participating in the transportation of explosives                                explosives.
have proper instruction in safety requirements                               (5) No metal tools, carbides, oils, matches,
and are held to account for all violations of                                    firearms, electric storage batteries,
procedure.                                                                       flammable substances, acids, or oxi-
   b. General Rules. The following rules are                                     dizing or corrosive compounds shall be
observed:                                                                        carried in the bed or body of any ve-
      (1) Vehicles used for the transportation                                   hicle transporting. explosives.
           of explosives shall not be loaded be-                             (6) Vehicles to be used in the. transporta-
           yond rated capacity and the explosives                                tion of explosives shall be in good
           shall be secured to prevent shifting                                  repair. When steel or part steel bodies
           of load or dislodgement from the ve-                                  are used, fire-resistant and nonspark-
           hicle in transit. In all open-body types                              ing cushioning materials shall be em~
           of vehicles the explosives shall be cov-                              ployed to separate the containers of
           ered with a fire-resistant tarpaulin.                                 explosives. from the metal.
                                                                             (7) Vehicles transporting explosives shall
      (2) All vehicles transporting explosives
                                                                                 be equipped with not less than two
           shall be marked with reflectorized
           placards on both sides. and ends with                                 fire extinguishers placed at strategic
           the word EXPLOSIVES printed on.                                       points, filled and ready for immediate
                                                                                 use, and of a make approved by the
      (3) Blasting caps or other initiators shall
                                                                                 National Board of Fire Underwriters
           not be transported in the same vehicle
                                                                                 for class Band C fires.
           with other explosives, if possible.
                                                                             (8) A vehicle containing explosives shall
           otherwise the caps should be carried
                                                                                 not be taken into 'a public building or
           in the front and the explosives in the
                                                                                 repair shop or parked in congested
           rear of the truck.
                                                                              / areas for any period of time.
      (4) All vehicles used for transportation
                                                                           /(9) All vehicles shall be checked before
                                                                                                                 AGO 7258A
               transporting explosives and all elec-     ally placed at locations determined according
              tric wiring completely protected and       to safety, accessibility, dryness, and drainage.
              securely fastened to prevent short cir-    Safety and accessibility, however, are the most
              cuiting.                                   important.     An ideal location is a hilly area
       (10) Vehicles transporting explosives shall       where the height of the ground above the maga-
              be operated with extreme care and          zine provides a natural wall or barrier to build-
              shall not be driven at a speed greater     ings, centers of communication, and other
              than 35 miles per hour. Full stops         magazines in the area. Sidehill dugouts are
              shall be made at approaches to. all        not desirable, as adequate ventilation and drain-
              railroad crossings and main high-          age are often hard to provide. Brush and tall
              ways, and the vehicle shall not pro-       grass should be cleared from the site to mini-
              ceed until it is known that the way is     mize the danger of fire.
             clear. This, however, does not apply           Table XV.      Magazine      Locations      (Unbarricaded)
             to convoys or protected crossings
             manned by highway flagmen or                Qantity. pounds       Minimum distance in feet from nearest-
                                                          of explosives
             guards.                                       (not over)        Inhabited          Magazine      Public highway,
                                                                              building                        railway, and/or
      (11) All vehicles transporting       explosives                                                         electric lines

           . on public highways, roads, or streets                50            300                50             180
             shall have an authorized driver and                 100            380                50             230
            helper. No person other than the au-               2,000           1010               140             610
             thorized driver and helper shall be            . 20,000           1950               300            1170
                                                            100,000            3630               510            2180
             permitted to ride on trucks transport-         225,000            4190               670            2515
             ing explosives or detonators.
                                                          Note. For more detailed information   see TM 9-1903, C I, 26 Febru-
                                                        ary 1957.
  142. Magazines
    a.. Types. Explosives are stored in maga-              d. Lightning Protection. All magazines must
 zines according to the safety. regulations pre-        have a grounded overhead lightning rod sys-
 scribed in TM 9-1903. Table XV indicates the           tem. Also, all metal parts-doors,   ventilators,
 minimum distance for the location of maga-             window sashes, and reinforcing steel-must be
'zines from other magazines, buildings, and             connected in several places to buried cond~its
 routes of communication based on the quantity          of copper-plate or graphite rods.
of explosives stored. There are two types of
magazines-permanent      and temporary.      Al-        143. Field Expedient Structures
though the permanent type is preferred, tem-               a. Field expedients for the storage of ex-
porary or emergency types are frequently                plosives when magazine construction' is not
required when permanent construction is not             possible are-
possible.                                                     (1) A dugout excavated in a dry area and
  b. Barricades. Explosives storage magazines                     revetted with timber to prevent
must be barricaded, that is, have a substantial                   caving.
obstacle between them and inhabited buildings.
                                                              (2) An isolated building.
For certain explosives, effective natural or
artificial barricades reduce by one-half the dis-             (3) A light wooden frame box house, with
tance necessary between magazines, railways,                      a 'wedge type roof covered by cor-
and highways.       The use of barricades thus                    rugated iron, or merely covered with a
permits the storage of larger quantities of ex-                   tent or canvas tarpaulin.      The ex-
plosives in any given area. Although barri- .                     plosives should be placed on pallets for
cades help protect magazines against explosives                   all-around ventilation.
and bomb or shell fragments, they are no safe-             b. Field expedient storage facilities should
guard against pressure damage.      .                   be appropriately marked by signs on all four
   c. Other C?onsiderations. Magazines are usu-         sides, and guarded.
AGO   7258A
    144. Temporary Magazines       and Storage         and other regulations (AR 385-63).
       Limited supplies of explosives can be stored .. 145. Destruction and Disposal of
    for several days when necessary in covered am-           Explosives .                   "
    munition shelters and should be so separated         a. Methods. Explosives, being insoluble in
    that fire .or explosion cannot be transmitted      water, generally cannot be disposed of as sew-
    from one shelter to another. Piles of explosives   age. Submergence, burning, or decomposition
    temporarily stored in the open should ~ontain      by chemical agents is necessary. Explosive
    no more than 500 pounds; and be placed no less" material may be disposed of without."    alteration
    tha~ 140 feet apart. Explosive' components         in form by dumping at sea. The best method
    should be piled separately. Explosives, caps,      of destroying explosives, however, is by burn-
    and other demolition material stored tempo-'ing.                                    '
    rarily in training areas should be kept .separate     b. Ordnance Units. Explosives are destroyed
    in covered ammunition shelters~ and under          by explosive ordnance disposal units as directed
    guard at all times. Temporary storage opera-       in AR 75-15, TM 9-1385-9, TM 9-1900,TM
    tions should be guided by local"safety SOP's       9-1903, and TM 9-1375-200.

                                                                                        )   .

    152                                                                                         AGO 7258A
                                         APPENDIX      A

  DA Pam 27-1       Treaties Covering Land Warfare.
  AR 75-15          Responsibilities   and Procedures      for Explosive Ordnance Disposal.
  AR 385-63         Regulations for Firing Ammunition for Training,         Target Practice, and
 SM 9-5-1375        Stock List of Current Issue Items-FSC Group 13 Ammunition and Ex-
                      plosives, Class 1375 Solid Propellants, and Explosive Devices .
. FM 5-15           Field Fortifications.
 FM 5-26            Employment of Atomic Demolition Munitions (ADM).
 FM 5-29            Passage of Mass Obstacles.
 FM 5-31            Boobytraps.
 FM 5-34            Engineer     Field Data.
 FM 5-35            Engineer's    Reference and Logistical Data.
 FM 8-10            Medical Service, Theater of Operations.
 FM 19-30           Physical Security.
 FM 20-32           Land Mine \Varfare.
 FM 20-33           Combat Flame Operations.
 FM 23-30           Grenades and Pyrotechnics.
 FM 31-10           Barriers and Denial Operations.
 FM 101-31-1        Staff Officer's Field Manual; Nuclear vVeapons Employment.
 TM 5-220           Passage of Obstacles Other than Minefields.
 TM 5-280           Foreign Mine Warfare       Equipment.
 (C) TM 5-280A      Foreign Mine WarefareEquipment            (U).
 TM 5-332           Pits and Quarries.
 TM 9-1300-206      Care, Handling, Preservation,      and Destruction of Ammunition.
. TM 9-1345-200     Land Mines.
 TM 9-1375-200      Demolition Materials.
 TM 9-1375-203-12   Operator and Organizational Maintena:nce" Manual:          lO-Cap Capacity
                      Handle Operated Blasting Machine.
 TM 9-1385-9        Explosive Ordnance Reconnaissance.
 TM 9-1900          Ammunition, General.
 TM 9-1903          Care, Handling,    Preservation,   and Destruction   of Ammunition.
 TM 9-1910          Military Explosives.
 GTA 5-10-9         Demolition Card.

 AGO   7258A                                                                                  153
                                                      APPENDIX B
                                      METRIC CHARGE CALCULATIONS

 1. Introduction                                                                           302         900
                                                                                K=         550   =550
    The following metric equivalent charge cal-
                                                                                K= 1.64 kg
 culation formulas   are included because of
 N ATO requirements, wherein the United States                                  Use of 1.6 kilograms                of. TNT
 and British Armies are gradually Ghanging
                                                                     b. Internal Charge.
.over from their tables of measurement to the                                                          D2
                                                                        Formula: K = 3500                    .
 metric system. Problems, solutions, and tables                                  K = kilograms of TNT requIred
 with measurements     converted to the metric                                   D = diameter of target in centi-
 system are given below.                                                                 meters
                                                                        Example: (fig. 96)
2. Structural Steel Cutting Formula
                    A                                                                      K= 3500
Formula:     K = 38
           K = kilograms of TNT required                                                   K=~=~
                                                                                                      3500      3500
           A = gross sectional area in square                                              K= .257kg
                   centimeters                                                             Use 260 grams of TNT or anY
  .Example: (fig. 97)                                                                        other explosive
       Flange Area = 2 X 1.2 X 12.7 = 30.48 or
       30.5 sq cm                                                  4. Breaching Formula
       Web Area = 28 X 1      28 sq cm                               Formula:  K = 16R3KC
       A (total) = 30.5 sq cm         +
                                28 sq cm = 58.5                                K = kilograms of TNT required.
          sq cm                                                                R = breaching radius in meters.
             A        58                                                       K = the material factor based on
       K=SS=3"8                                                                       strength and hardness of
       K = 1.5 (use 1.5 kilograms            of TNT)                                  mate'rial to be demolished.
                                                                               C = the amping factor based on
 3. Timber Cutting Formula                                                      .     type. and extent of tamP-
   a. External Charge.                                                                ing to be used.             d
                           D2                                                      Add 10 percent to calculate .
       Formula:   K = """5so-
                                                                                      charge less than 22.5 kilo-
                 K - kilograms of TNT required
                                                                                      grams.      .
                 D = diameter of target in centi-                                  For. walls 30 centimeters
                                                                                       (approx 1 ft) thick or .le~o
       Example: the diameter of a tree is 30 centi-
         meters.                                                                      increase the. charge by

              Table XVI.        Value of Material   Factor K for Calculation

                                                                                of Breaching          Charges   (Metric)
                                                                               Breaching    ra~lius                           K
 Ordinary earth                                             _
                                                                All values                                                 0.05
 Poor masonry, shale and hardpan, good timber, and
    earth construction                           _
                                                                All values                                                 0.23
                                                                                                                              AGO 725S~
                                    Material                                                    Breaching    radius                                  K

 Good masonry,        ordinary       concrete,   rock                         Less than 1 meter                                                 0.35
                                                                               1 to less than 1.5 meters                                         .28
                                                                               1.5 to less than 2 meters                                          .25
                                                                              More than 2 meters                                                 .23
 Dense concrete,      first-class      masonry                      "__ ~_    Less than 1 meter                                                 0.45
                                                                              1 to less than 1.5 meters                                          .38
                                                                              1.5 to less than 2 meters                                          .33
                                                                              2 or more meters                                                   .28
 Reinforced     concrete     (will not cut steel reinforcing)          __     Less than 1 meter                                                 0.70
                                                                              1 to less than 1.5 meters                                          .55
                                                                              1.5 to less than 2 meters                                          .50
                                                                              2 or more meters                                                   .43

      a. Breaching Radius.    The breaching radius                                                           ground, fig. 105)
   (R) is the distance in meters which an ex-                                                          K= 16R3KC
- plosive charge must penetrate and within which                                                       K = 16 X3.3 X .33 X 4.5
  all material is displaced or destroyed. For ex-                                                      K = 78.4 or 78.5 kilog"rams of
  ample, to breach a 2-meter concrete wall by                                                                TNT per charge
  placing a charge on one side, the value of R                                      5. Additional- Data
  in the formula K = 16 R3KC is 2 meters.                                              Characteristics  of U.S. explosives, steel
     b. Material Factor. The values of the ma-                                      cutting charges, and minimum safe distances,
  terial factor for various types of construction                                   expressed in the metric system, are given in
  are given in table XVI.                                                           tables XVII, XVIII, and XIX respectively.
     c. Tamping Factor. The value of the tamp-                                         Table XVII.           Characteristics of Principal U. S.
 ing factor depends on the location and the                                                                  Explosives (Metric)
 tamping of the charge. No charge is consid-
                                                                                                             Velocity of
 ered fully tamped unless it is covered to a                                                                 detonation     Relative           Weight
                                                                                                                                              per block
                                                                                             Name            (meters per effectiveness
 depth equal to the breaching radius: If under-                                                                  sec)

 water demolition is necessary, the tamping
                                                                                    TNT      --------            6,900         1.00      .454 and
 factor for placement of charges tamped with
                                                                                                                                            .227 kg
 earth is used (fig. 105).                                                                                                     1.20      1.1 kg
                                                                                    Tetrytol   ------            7,000
        Example: Determine the amount of TNT                                        M1l8 (sheet                  7,190                     .90 kg-block
                  required to breach a dense con-                                     explosive) .
                                                                                    Composition                  7,625        -1.34      0.22 kg-sheet
                  crete pier 1.5 meters thick with
                                                                                      C-3.                                                1.02 kg-M3
                  untamped charges placed on the                                                                                          1.1 kg-M5
                                                                                    Composition                 8,040         1.34
                  ground.                                                             C-4.                                               1.1 kg-M5Al
                     R = 1.5 meters                                                 Ammonium                    3,400         0.42       0.56 kg-M112
                     K = .33 (dense concrete, ta-                                     nitrate.                                           18.17 kg
                                                                                    Military                    6,100         0.92       .227 kg
                     C = 4.5 (untamped, on the
                                               Table XVIII.       Steel Cutting Charges (Metric)
        A verage thickness                         Kilograms    of TNT for rectangular.      steel section of given dimensions
           of section in
            centimeters                                               Width    of Sections     in Centimeters

                                                                                                 30.5     35.6        40.6    45.7    50.8    61.0
                              5.0        7.6     10.2    12.7      15.2      20.3     25.4
                                                                                                    .54       .64       .73     .82     .91   1.1
         .64                   .09        .14      .18     .23        .27       .36      .45
                                                                                                    .77       .91     1..04   1.18    1.27    1.54
         .95                   .14        .23      .27     .32        .41      .54      .64
                                                                                                  1.04      1.22      1.36    1.5     1.7     2.0
       1.27                    .18        .27      .36     .45       .54       .68      .86
                                                                                                  1.32      1.5       1.7     1.95    2.13    2.59
       1.59                    .23        .32      .45     .54       .64       .86     1.1
                                                                                                  1.54      1.81      2.04    2.31    2.59    3.08
       1.91                    .27        .41      .54     .64       .77      1.00     1.27
                                                                                                  1.81      2.08      2.4     2.7     3.0     3.6
       2.22                    .32        .45      .64     .77       .90      1.22     1.5
                                                                                                  2.0       2.4 .-    2.7     3.1     3.4     4.1
       2.54                    .36        .54      .68     .86      1.04      1.36     1.7

AGO   7258A
                             Table XIX.   Minimum    Safe     Distarl;ces (in the Open)      (Metric)

           Kilos of explosives                Safe distance                   Kiloi:l of explosives              Safe distance
                                                in meters                                                          in meters

.45 to 12 kilos ----------------------              274           34 --------------------------------                 384
13 -------------------------------                  281           36 -------------------------------                  393
14 -------------------------------                  290           40 ------- --- - --------- -- _. -- -- -----        410
16 -------------------------------                  302           45 -------------------------------                  424
18 -------------------------------                  .311          56 -------------------------------                  457
20 -------------------------------                  320           62 -------------------------------                  486
22 --------------------------------                 329           90 --------------------------------                 534
23 ----------------~---------------                 337          136 -------------------------------                  612
25 -------------------------------                  348          181 --------------------------------                 673
27 -------------------------------                  357          226 -------------------------------                  726
29 -------------------------------                   366         Over 226 (compute by formula)

156                                                                                                                     AGO 7258A
                                            APPENDIX C
                                   AS DEMOLITION CHARGES

  1. Introduction                                                     Type    Mine                         Explosive
                                                      M7A2 AfT (metallic)                         3% lb TNT
    When land mines, aerial bombs, and shells         M6A2 AfT (metallic)                         12 lb TNT
 are used as demolition charges, special precau-      M15 AfT (metallic)                          22 lb TNT .
 tions must be taken because of flying steel frag-    M19 AfT (nonmetallic)                       21 lb TNT
 ments. The use of such mines, bombs, and             M21 AfT (metallic)                          10% lb composition H6
 shells is generally uneconomical but may at                  (2) Foreign Mines
 times become necessary or desirable. Such                       (a) Austria
                                                      Barrier       AfT      (metallic)           10Ib
 material may be issued from captured or
                                                                    (b) Belgium
 friendly supply stocks or, in the case of land       Model VI AfT (metallic)                     6 lb
 mines, may be those recovered from enemy or          BSB AfT (metallic)                          7.75 lb TNT
 friendly minefields. In no case should unex-         Type H AfT (metallic) --                    12.75 lb TNT
 ploded dud shells or bombs be used for demoli-       Type HA AfT (metallic)                      12.75 lb TNT
 tion purposes.                                                     (C)      Co'mmunist       China
                                                      Dual purpose No 8
 2. Land Mines                                          (metallic) .                              5 lb
    a. Safety              Only defuzed mines
                 Precautions.                         Dual purpose No 4
                                                        (metallic).                               12 lb
should be used in demolition charges, as fused
                                                      Model 1951 AfT (wooden)                     13.8 lb TNT
mines recovered from minefields may be sensi-                       (d) Czechoslovakia
tive because of near misses and may be deto-         PT-Mi-K AfT (metallic)                       11 lb TNT
nated by even normal handling. The use of            PT-Mi-D AfT (wooden)                         6 lb TNT (approx)
enemy mines salvaged from minefields or              PT-Mi-Ba AfT                                 15 lb cast TNT
dumps is regulated by directives issued from           (plastic or bakelite).
headquarters of the theater concerned. United                       (e) Finland
                                                     M 36 AfT             (meta1lic)              8 lb TNT
States and foreign land mines are described in       M 39 AfT             (metallic)            :-8.8 lb TNT
detail in TM 9-1345-200, TM 5-280, and TM                           (f) France
                                                      M1935 heavy AfT
   b. Charges. In calculating demolition charges     . (metallic).                               3.25 lb
                                                      M1936 light AfT
 when using mines, only the explosive weight is         (metallic) .                              5.75 lb
 considered. Normal explosive quantities may          M1948 AfT (metallic)                _______ 11.5 TNT or MD (20%
 be used for cratering or pressure charges with                                                      dini trona pthalene
mines; but, because of poor contact of the mine                                                     and 80 % picric
case against irregularly shaped objects, it may
                                                     M1948 plate charge
be necessary to increase cutting charges con-         AfT (metallic) ..                          16 lb TNT or
siderably. Test shots will determine the re-                                                       picric acid*
sults to be obtained under given conditions. A       M1951 shaped charge
list of antitank mines in current use by. the         AfT (metallic).                            4 to 5 lb hexolite
                                                     Model 1947 AfT (plastic)                    12.1 lb TNT
United States and (in current use or obsolete in     Model 1951 AfT (Caseless)                   16-20 lb cast TNT
foreign armies) with their explosive weights                    (g) Hungary
is given below. Information, however, on the         CVP-1 variable pressure,
type of explosive used is not always available-       general purpose (metallic).                3.5 lb TNT
      (1)    United States                           See footnote     on page    158.

A.GO 7258A                                                                                                             157
             Type    Mine                               Explosive                  . c. Priming. Land mines are detonated by
           (h)      Japan       (WW 11)                                          means of a pound of explosive placed on the
 Type 93 antivehicular
   (metallic).                                  2 lb picric     acid*
                                                                                 pressure plate. If larg'equantities of mines are
 Yardstick     antivehicular                                                     to be fired simultaneously, several mines are
   (metallic).                                  6 lb picric     acid*            primed to insure complete detonation. Deto-
 Model 1 beach mine                                                              nation of a single mine normally detonates
   (double horn) (metallic) •                   40.6 lb trinitroanisol
                                                                                 other mines in contact with it.
 Model 2 beach mine (single
, horn) (metallic).                             22 lb
                                                                                 3. Aerial Bombs
           (i)      Netherlands                                                    , a. Use. General-purpose aerial bombs may
Type II A/T (metallic)                          9Ib                              be used satisfactorily as demolition charges but
Mushroom-topped    dual
                                                                                 are more effective as cratering charges. Their
  purpose (metallic).                           5.25 lb TNT
                                                                                 shape makes them inefficient for demolitions
           (j)      South Korea                                                  requiring close contact between the explosive
Heavy AfT mine (metallic)                     __ 22 lb TNT                                                            be
                                                                                 and the target .. Precautions must _' taken, to
Type I dual purpose
  (metallic).                                 -5.7    lb flaked TNT
                                                                                 avoid damage to installations and injury to
Type II dual purpose                                                             personnel because steel fragments of the bomb
  (metallic) •                                  4.5 lb TNT,                      case are thrown great distances. Before using
           (k)' USSR                                                             a bomb, it must be positively identified as a
PMZ-40 A/T (metallic)                           8 lb
                                                                                 general-purpose bomb.                 .
TM-35 A/T (metallic)                            8.8 lb                               b. Charges. The explosive content of bombs'
TM-38 AfT (metallic).                     .     6.5 lb                           is approximately half their total weight. Table ,
TM-41 A/T (metallic)                            8 lb amatol 80/20 or             XX'gives the weight of high explosive in vari-
                                                   flaked TNT (picric            ous types of general-purpose bombs. Approxi-
                                                   acid * booster)
  T-IV AfT (metallic)                           6.2 lb                           nlately 20 percent of the explosive power is                      c

  AKS general purpose                                                            expended in shattering the case.
.    (metallic) •                           13.2 lb
                                    _______ 11-15 lb pressed
                                                                                   Table XX.    Explosive Content of General-Purpose.
  TMD-B AfT (wooden)
                                                  amatol, dynam-
                                                  monite,cast  TNT,
                                                  or powdered picric
 TMB-44      AfT      (wooden)       _~         11-15.4 Ib amatol,                 100-lb   GP, AN-M30A1                115                   57
                                                  dynammonite,     or              250-1b   GP, AN-M57 A1               260                 125
                                                  TNT                              500-1b   GP, AN-M64A1                 525                266
TMB-2A/T             (tar-impregnated           11 lb powdered amatol            1,OOO-lb   GP, AN-M65A1                 990                555
  cardboard).                                     80/20                          2,000-lb   GP, - AN-M66A2             2,100               1,098
TMS-B A/T            (tar-                      13 Ib powdered amatol        .   3,000-lb   GP, T-55                  ,2,605               1,710
  impregnated          cardboard).                80/20

            (l) United Kingdom'                                                     c. Priming. Bombs under 500 pounds weight
Mark     2 EP A/T           (metallic)    --_4.5 Ib TNT                          are detonated by firing a 5-pound explosive"
Mark     2 GS A/T           (metallic)        4 Ib TNT or baratol                charge in good conbtct' in the middle of the
                                                  (barium nitrate and            case. Bombs of 500 pounds or more are deto- '
                                                  TNT-20/80   or                 nated by a 10-poundcharge similarly placed.
 Mark 3    GS       A/T     (metallic)         4.5 lb TNT                        Fuses should not be positioned on the nose or
 Mark 4    GS       AfT     (metallic)        8.25 Ib TNT                        tail. To insure detonation~ large bombs should
 Mark 5    GS       A/T     (metallic)        4.5 lb TNT                         be primed separately. -
 Mark 5    HC       AfT     (metallic)        8.3 Ib TNT
 Mark 6    EP       and                                                          4. Artillery Shells (Nonnuclear)
   Mark    5 C      AfT     (metallic)          4.5 TNT
                                                                                    Artillery she'Us ~re u~ed for demolition only
    lit Picric acid. corrodes metals, forming  extremely    sensitive com-       where a fragmentation effect is desired" Be-,
 pounds, easily detonated.    Mines loaded with this explosive should not
 be handled except to move them to a safe disposal area for destruc-             cause of their low explosive content they are
 tion.                                                                           seldom -used for other demolition purposes ..Th,e
 158                                                                                                                              AGO 7258A
105-mm howitzer HE shell, which weighs 33         should be placed on each shell. The universal
pounds, contains only 5 pounds of explosive;      destructor M10 (para 40a) may be used to
while the 155-mm howitzer shell contains only     detonate projectiles or bombs that have 1.7- or
15 pounds. Shells up to 240-mm are detonated      2-inch diameter threaded fuse wells.        The
by 2 pounds of explosive placed in good contact   booster cavities of bombs and large projectiles
with the case, just forward of the rotative       should be filled to the full depth by adding
band. To insure complete detonation, a charge     booster cups to the destructor M10 as required.

                                                  APPENDIX D
                        SUMMARY      OF EXPLOSIVE .CALCULATION FORMULAS ,..""."

1.    Timber-Cutting      Charge's                                 high), use 1 pound of explosive.
 . a. External       Charges, Untamped       (para 78a).     e. Saddle Charge (para 83b) .
             n 9
                                                                Base of charge = 1;2 circumference of
           40                 • d                                 target (fig. 100).
       P = pounds of TNT requIre
                                                                Long, axis of charge = circumference of
       D = diameter of the timber in inc,hes or                   target
                 the least dimension of dressed tim-
                 be~                     .                      Thickness of charge = 1/3 thickness of
                                                                  M5A1 block (2/3 inch) for targets up
  b. Cutting Trees to Create an Obstacle (para
78b).                                                             to 19 inches in circumference (6 inches
                                                                  in diameter) ; Ih the thickness of M5Al .
     c. InternalCharges, Tamped (para 78c).                       block (1 inch) for targets from 19 to 25
            n  9

        P=50                                                      inches in circumference (over 6 to 8
        P = pounds of any explosive                               inches in diameter).            '
                                                                      Note. Steel alloy targets over 25 inches 1
      . D = diameter, or" the least cross-sectional
                                                                   circumference (over 8 inches in diameter) _r~.            _
              dimensional in inches.                               quire the diamond charge.
2. Steel-Cutting Charges                                     f. Diamorid Charge (para 83c).
     a. Structural Members (para 81b(1».                         Long axis of charge = circumference' of
       P=%A                                                        target (fig. 101). '
       P = pounds of TNT required                                Short axis of charge = Ih circumference
       D = cross-sectional area in square inches                   of target     !          ,        .             .'

            , of the steel member to be cut. .                   Thickness of charge =1/3 thickness M5Al
                                                                   block (2/3 inch)
     b. Other Steel Members  (para 81b(2) (a».
                                                              g. Ribbon Charge (para 83d).~
                                                                 Thickness of charge ==== 34 thickness of
       P = pounds of TNT required                                  target (fig. '102)               .
       D = diameter, in inches, of section to be                 Width of, charge - 3 X thickness
                                                                         <                             of
     c. Steel Bars 2 Inches in Diameter          or Less        Length of charge - length._of cut.
(para 81b(2)(b».
       P=D'                                                3., Pressure Charges
       P = pounds of TNT required                               (para 84)
      D = diameter of bar in inches or largest                  P-3H~                                             _
              dimension of section to be cut.                    P = pounds of TNT 'required for each
     Rule of thumb.                                                      stringer'.                 '.
       Bars up to 1 inch in diameter, use 1 pound                H     height of stringer, including thICk..
         TNT.                                                            ness of roadway, .            _.. t
       Bars over 1 inch in diameter and up to .2                 T = thickness in feet of _stringer in fee
         inches, use 2 pounds TNT. ,                           The values ofH and T, if not whole numbersi
     d. Railroad Rails.     '                              -are rounded off to the next higher quart~r-food
       To cut 80-pound or lighter rail (5 inches or         dimension. Neither H nor T is ever considere
         less in height), use lh pound of explosive         to be less than 1 in the formula.'               ,
                                                            ' Note. ,-Increase' the calculated   charge        P by one-,
       To cut rails over 80 pounds (over 5 inches
                                                           third if it is not tamped.
160                                                                                                       -'    .AGO 7258A
4. Breaching Charges                                            40 pounds of explosive, and on the enemy side,
  a. Size of Each Charge (para 86a).                            4 feet deep and loaded with 30 pounds of ex-
    . P=R3KC                                                    plosive. Row on enemy side is detonated first
      P = pounds of TNT requi~ed.                               and on the friendly side, 112 to 1~ seconds later.
      R = breaching radius in feet (rounded off                    d. Angled Crater (para 91b).         A line of
            to the next higher 1h-foot).                        boreholes is blasted or drilled across a roadway
     K = material factor (table XI).                            at a 45° angle (fig. 110). Standoff distance for
      C = tamping factor (fig. 105).                            M2A3 shaped charge for boring holes on un-
                Note. Add 10        percent to the calculated   paved roads is from 20 to 30 inches; and on
              charge whenever       P is less than 50 pounds    paved roads, about 36 inches.         Increase in
              and increase the      charge by 50 percent for    standoff distance increases depth of borehole
              walls 1 foot thick     or less.
   b. Number           of Charges     (para 87b).               but decreases its diameter.
                 w                                              6. Breaching Hard-Surfaces Pavements
          2R                                                       Charges are computed on the basis of 1 pound
      N = number of charges                                     of explosive per 2 inches of pavement thick-
      W = width of pier, slab, or wall in feet                  ness. Tamping should be twice the thickness of
      R = breaching radius in feet                              the pavement (para 88b (2) ).
   When the value of N has a fraction less than
                                                                7. Computation of Minimum Safe
1;2, the fraction is disregarded, but when the
fraction is 1h or more, the value is rounded off
                                                                   a. For charges less than 28.pounds, the mini-
to the next higher whole number. An excep-
                                                                mum safe distance is 900 feet. This, however,
tion to the general rule is the N-value between
                                                                gives no insurance against missile hazards,
1 and 2, wherein a fraction less than ;4. is dis-
                                                                which require a defilade.
regarded, but a fraction of 14 or more is
                                                                   b. For charges from 28 to 500 pounds, the
rounded off to the next higher whole number, 2.
                                                                safe distance is computed by means of this
5.Cratering      Charges                                        formula:
   a. Deliberate   Method    (para 89).    Forty-                     Safe distrnce in feet =
pound cha~ges in 5-foot boreholes are alter-                                 3
                                                                       300 vpounds of explosive
nated     with   80-pound    charges   in 7-foot
                                                                  c. For quarrying operations the formula is:
boreholes. All boreholes are placed on 5-foot
                                                                     Safe distance in feet = .
centers. The end holes in all cases are 7 feet
~eep.No      two 5-foot holes should be adjacent                       350 vpounds    of explosive
to each other (fig. 107).
   b. Hasty Method (para 90). Ten pounds of                     8. Notes
explosive per foot of borehole is placed in holes                 a. The charges calculated by the above for-
of equal depth. Boreholes are positioned on                     mulas should be rounded off to the next higher
5-foot centers at depths varying from 21;2 to 5                 unit package of explosive being used or cut,
feet (fig. 108).                                                when applicable.
   c. Relieved Face Crater (para 91a).       Two                   b. When an explosive other than TNT is used
rows of boreholes are drilled 8 feet apart (fig.                in external charges computed from the steel,
109) ; boreholes are spaced on 7-foot centers-                  timber, breaching, or pressure formula, the
four on the friendly side and three staggered                   value of P should be adjusted by use of the
between them on the enemy side. Boreholes on                    relative effectiveness factor as indicated in
friendly side are 5 feet deep and loaded with                   table VIII.

AGO   7258A                                                                                                   161
 323-561 0 - 68 - 11
                                                             APPENDIX      E
                        POWER              REQUIREMENTS          FOR SERIES FIRING              CIRCUIT

1. Series Circuit                                                     3. Electric Power Formula
   In demolition projects, electric blasting caps                        Electrical power is computed by means of the
are connected in series and fired by an elec-                         following formula:
tric power source (blasting machine) . A                                    W    =    J2R
series circuit provides a single path for the                               W    =    electrical power, expressed in wattS.
electrical current which flows from one firing                               I   =    current, expressed in amperes.
wire through each blasting cap to the next                                  R    =    resistance, expressed in ohms.
blasting cap and back to the other firing wire.
A series circuit should not contain more than                         4. Electrical Characteristics       of Electric
 50 blasting caps. The connection of more                                Blasting Caps
than 50 caps in a series circuit increases the                           The current needed to fire military electric
hazard of breaks in the firing line or cap leads
                                                                      blasting caps connected in series should be at
prior to the initiation of some caps.
                                                                      least 1.5 amperes regardless of the number of
                                                                      caps. The resistance of a military electric
2. Ohm's Law                                                          blasting cap is 2 ohms.
   The amount of voltage necessary to detonate
the blasting caps in these circuits is calculated                       5. Resistance of a Circuit
by the use of the basic law of electricity, Ohm's                        Resistance is computed to insure that the
Law-                                                                  power source is adequate to nre all charges
       E    = IR                                                      connected to the circuit. Both. the blasting
       E    =   electrical potential, or voltage, ex-                 caps and the wire contained in a circuit con-
                  pressed in volts.                                   tribute to the total resistance of that circuit.
       I   =    current, expressed in amperes.                        This resistance is computed from the individual
       R   =    resistance, expressed in ohms.                        resistances of the blasting caps and the wire.

                                 Table XXI.          Resistance of Various Sizes of Copper Wire

                 1                                       2                        3                              4

                                Size   0   copper wire
      AWG    (B&S)   gage No.                                                Length of                    Resistance of
                                                  Diameter                  wire to weigh
                                                    (in.)                                                 1,000 feet of
                                                                                1 pound                   wire (ohms
                                                                            (ft. per lb.)
     -----------------------                         3/10                             5.0
                                                                                                          per 1.000 ft.)
     -----------------------                         1/4                              7.9                            .3
     -----------------------                         1/6                          12.6                               .4
     --------------------~--                         1/8                          20.0                               .6
     -----------------------                         1/10                         31.8                           1.0
     -----------------------                         1/12                         50                             1.6
     -----------------------                         1/16                         80             .               2.5
     -----------------------                         1/20                        128                             4.0
     -----------------------                         1/25                        203                            6.4
     --------------~--------                         1/30

                                                                                 323                           10.2
                                                                                                                           AGO 7258A
The resistance of the wire used is a circuit de-                         1,000 feet of wire is used in the above com-
pe"nds upon its size and the length. Table XXI                           putation.

gives the resistance per 1,000 feet of various                      (3) Voltage:
                                                                         E = IR (para 2 this app)
sizes of copper wire. The total resistance in a
series circuit is the sum of the resistance of the                      "E = 1.5 X 46.4 = 69.6 volts
various components of that circuit.      (For sim-                  (4) Power:
                                                                        W = PR (para 3 this app)
plicity of calculation in the field, only the
resistance of the blasting caps is used to deter-                        E = 1.52 X 46.4 = 2.25 X 46.4 =
mine the resistance of a circuit.)                                       E = 1.52 X 46.4 = 2.25 X 46.4 =
                                                                               104.4 watts
 6. Calculations for a Series Circuit
                                                               7. Calculated Voltage Drop
    Complete calculations for any circuit involve
                                                                  In each of the examples given above the
 the determination of the current (amperes),
                                                               voltage drop (IR) in the blasting circuit was
 the voltage (volts), and the power (watts)
                                                               calculated by the use of Ohm's Law. In prac-
.needed to fire the circuit. Computation of the
                                                               tice, if the calculated voltage drop exceeds 90
 voltage and of the power requires the determi-
                                                               percent of the available voltage, it is. recom-
 nation of the resistance (ohms) in the system.
                                                               mended that the resistance of the circuit be
    a. Current Requirements. The current re-                   decreased or the voltage be increased.
 quired for a series-connected system of special
 electric blasting caps is 1.5 amperes, regardless             8. Capacity    of Power      Sources
 of the number of blasting caps in the circuit.
                                                                 a. Determining Capacity of Power Sources.
    b. Resistance. The resistance of the system                It is possible to determine from the nameplate
 is computed as described in paragraph 5 of this               amperage and voltage rating whether the
 appendix.                                                     power source is suitable. for firing an electric
    c. Voltage Requirements.        Using   Ohm's              circuit computed by the above methods. Fre-
 Law, E = IR (para 2 this app), the voltage                    quently, however, the size of a circuit that may
 needed is computed by multiplying the required                be fired with current from a given power source
 current (1.5 amperes) by the resistance of the                may be determined by consulting table XXII
 system.                                                       which gives the maximum capacities of some
    d. Power Requirements. By means of the                     power sources. If it is necessary to calculate_
 electrical power formula, W = J2R (para 3 this                the capacity of a given generator from the
app), the number of watts of power needed may                  nameplate data, proceed as follows:
be found by multiplying the square of the cur-                       (1) Divide 90 percent of the voltage of
rent required (1.52 = 2.25) by the resistance                             the generator (para 6 this app) by the
of the system.                                                            total amperage of the circuit, 1.5
    e. Illustrative Problem. Determine the cur-                           amps, to determine the maximum re-
rent, voltag~, and power required to detonate                             sistance in ohms that may be in the
the blasting caps of a circuit consisting of 20                           circuit.
special electric blasting caps connected in series,                  (2) Subtract the total wire resistance
and 500 feet of the standard 2-conductor, 18-                             from the maximum allowable circuit
gage firing wire.                                                         resistance of caps to determine the
                                                                          maximum allowable resistance of the
       (1) Current required = 1.5 amperes (a
            above)                                                        cap~ in the circuit.
       (2) Resistance:                                               (3) To calculate the maximum number of
                                                                          caps, divide the allowable resistance of
            20 blasting caps = 2.0 X 20 =40
                                                                          the caps in the circuit by the re-
            1,000 feet No. 18 wire (table XXI) =
                                                                          sistance of one cap (2.0 ohms).
            Total resistance = 46.4 ohms
                                                                  b. Illustrative    Problem. Determine        the
                Note. As 500-foot firing wire consists of      number of military electric blasting caps in
              2 strands   of No. 18 wire each 500 feet long,   series that may be fired by a 220-volt, 13th

AGO   7258A                                                                                                     163




                 AGO 7Z58A
                                       v       the series circuit -   126.9 -   63.4 or 63
                                           -                           2.0 '
                                         \caps (a(3)-above).
                                   c. Use'o!.Storage Batteries and Dry Cells.
                                The, size 'of a ,'circuit that may be fired by a
                                battery or dry cell may be determined by fol-
                                lowing the same procedure as that outline'd' in
                                a (1) through (3) above.
                                 , ..Caution': For safety, disconnect the battery
                                terminal prior to disassembly of the equipment
                                where there is danger from shorting across the
                                battery, circuit. ,In reassembly, 'make the bat- ~
                                h~ry terminal connection last.                    ,-

                 ~.. 'r   .;.

            .~   :

                                                   .l J


AGO 7258A                                                                             165
                                                           APPENDIX            F
                           SPECIAL      DEMOLITION                MATERIALS           AND          TECHNIQUES

                                               Section     I. SPECIAL CHARGES
 1. Square Charge                                                                   of the target above the base to obtain
   a. Description. This technique is applicable                                    the maximum results. A small charge
 to the demolition of concrete and masonry                                          may be taped to the target or sup-
 bridge piers and other types of construction,                                     ported by a platform. Larger charges
 but not steel. The charge for use on rein-                                        may be supported by strips of ma-
 forced concrete walls up to 4 feet thick is com-                                  terial and wire attached to the pier by
 posed of composition C 4 blocks, 2 x 2 x 11                                       fasteners driven into the concrete by
inches. They are placed as removed from the                                        means of the powder-actuated driver.
 packing case. For walls from 5 up to 7 feet                                   (2) Initiate the charge from the center
thick, haversacks of 8 blocks of C 4 (M5A1)                                         (fig. 121).
explosive, measuring 4 x 8 x 11 inches each                                    (3) Mud tamp the explosive on I-foot
may be used. The blocks are not removed from                                       thick targets, as this permits a 30-
the ha versacks, as they are easily fastened                                       percent reduction in explosive weight.
against the target (fig. 121). The size of the
charge depends on the thickness of the target                              c. Charge Size.
and the ratio of the thickness of the charge                               Concrete   thickness          Charge size          Charge    thickness

and the contact area. Although these charges ,                                1 ft                2 C4 blocks                 One block-2           in
If square, are 'more effective than if rectan-                                2 ft                4 C4 blocks                 One block-2           in
gular, it is not always feasible to cut them to                               3 ft                7 C4 blocks                One block-2            in
size. As most charges are rectangular, addi-                                  4 ft            20 C4 blocks                   One block-2            in
tional explosive is allowed for modification in                               5 ft                6 M37 kits (20 lb          One kit-4        in
technique. The charges tabulated in c below ,                                                        packet)
have proved effective.                                                        6 ft                8 M37 kits (20 lb '        One kit-4        in
    b. Placement on Piers.                                                                           packet)
                                                                              7 ft            12 M37 kits (20 lb             One kit-4        in
       (1) Place the charge at least the thickness

2. Foxhole              Digger   Explosive      Kit
    a. Characteristics (fig. 141)
      ,(1)    Case
             Material                            Shape                                                                                              -
Plastic with screw cap.             Tubular    with   truncated     top.

                                                                                   7.38 x 2.28 in

                                                                                                                             . 1.0 lb
       (2) Shaped Charge

             Material                  Shape                 Size                                     Explosive   Charge
Copper cone with 60°             Tubular with            7.37 x 2.0 in

                                                                                                   Det Vel

                                                                                              27,559 ips

                                                                                                                  118g (4.16

  angle; and plastic.              truncated top.
                                                                                                                                        AGO 7258A
       (3) Crate ring Charge

            Material               Shape                Size                                                  Explosive   Charge

                                                                                    Type              Det Vel                  Wt.        Booster

 2 segments of pressed             Tubular            8.21 x 1.0 in              PBXN-1            24,606 fps         162g (5.71          RDX
   explosive; connecting                                                                                              oz)

      (4) Fuzes

       Material            Shape              Size                      Action                 Initiation             Safety         Explosive

Stainless   steel      Tubular        4.25 x 0.56 in     Mechanical with                     Push button           Cotter      pin   RDX and
  body; steel                                             spring-driven                                                                primer.
  coupling.                                               striker

      (5) Auxiliary        items

 Piece of No.9 nylon twine 36 in long; steel stability rod 4.25 x 0.1 in; two strips adhesive-coated foam tape;
 and lug on side of case with hole for stability rod and a ring for attaching" kit to soldier's clothing or equip-

      (6) Remarks

  Outer case of kit serves also as standoff for shaped charge.


                                                               (I)   REMOVE All PARTS FROM INSIDE CONTAINER
                                                               (2)   lEAVECAP OFF

                                           Figure 141. Foxhole digger explosive kit.

  b. Effect.                                                                               at. the top and 1 inch at the bottom.
     (1) The shaped charge will penetrate soil,                                            It will bore a hole through 5-inch mild
         depending on the density, to depths                                               steel plate, 1 inch in diameter at the
         varying. from 20 to 33 inches, forming                                            entry and 14 inch at the exit, and will
         a tapered hole 214 inches in diameter                                             penetrate .concrete to a depth of 8

AGO 7258A                                                                                                                                        167
                     CRATERING : BORING HOLES
                                                                       {FUZE SlEEVE
                                                 MATING     TERMINAL


         SUPPORT CONTAINER       UPRIGHT                .

                                         RED   SECIION1
                                               LUG WITH HOLE

       HUNDRED    FEET





                                 A 5-FT DIAMETER
                               CONTAINER    WITH
                                                    CIRCLE                  15YDS . M INIMUM4.
                                                                                      .     ,-
                                                                                                                        '--       '~>-rE:." '. .
                                                                                                                                                    \L.        b~
                                                                                                                                                                         "<.':-                /

       LUMINOUS   MARKER.                                                              ".                                                                      .......                   ,,"
                                                                                            ...... ,"   .~   -'   - .         ',' .   ';       ..   ~#!,                          ..'"

                                                                                 5FT DIA: NIGHT                               FINDER"
                                                                             ,;\ MARK

           Figure 142.    Arming and placement of foxhole digger explosive kit for cratering.
                                                                  ?               ?           •

168                                                                                                                                                        v         AG07258A
                             CRATERING: EM~LACEMENT                    AND

                                                               FUZE SLEEVE

                     A. AFTER SHAPED CHARGE HAS DUONA TED,
                        RETURN TO FOXHOLE    SITE.CONNECT
                        SECTIONS OF CRA TERING CHARGE. PUSH
                        TOP OF CRATERING  CHARGE
                                                          THE           .

                                                                            1       '
                                                                                 MATING   TERMINAL

                       HAND AND PLACE ASSEMBLY INTO HOLE.
                       WITH RIGHT HAND REMOVE COTTER PIN
                       AND SAFETY SLEEVE, AND WITH THUMB
                       PUSH FIRING BUTTON. THEN DROP       ,
                       ASSEMBLY TO BOTTOM    OF HOLE

                       CAUTION: AFTER PUSHING BUTTON, DO NOT
                       AND MAY BE HOT ENOUGH     TO BURN YOU

                                              r--    15 YDS MINIMUM    I

                    C. DURING THE 20    - SECOND   DELAY TIME
                       PROCEED TO A    DIST ANCE OF NO LESS THAN
                       15 YARDS AND    LIE DOWN ON BELL Y WITH
                       OVER EARS

                       SHOVEL OUT LOOSE    SOIl,AND FINISH FOXHOLE
                       AS REQUIRED                     .

                                           Figure 142-Continued.

         inches with a hole 11M. inches in di-            charge (5.71 ounces of explosive) may be use-
         ameter at the top and lh inch at the             ful in boring small holes in metal, concrete,
         bottom.                                          wood, and soil, and in cutting small steel bars,
     (2) The cratering charge will form a                 rods, and cables. This, of course, depends on
         crater in soil about 42 inches in di-            the ingenuity and initiative of the experienced
         ameter and about 32 inches deep.                 demolitionist.  It may be useful to damage
  c. Use. For demolition purposes the shaped              metal working parts of vehicles and other

AGO   7258A                                                                                            169
                               SHAPED CHARGE

                                                 FUZE SLEEVE

          WITH THUMB

                                                SAFETY SLEEVE

                                                 FIRING   BUTTON




                                                                                                            ."...----   ...........

                                                                                              /'                                      "-
                                                                                 I /ADHESIVE                        TAPE
       F. SHAPED CHARGE MA Y BE USED TO DAMAGE                           I                ~~
          ENEMY TANKS AS SHOWN                                           I                I          .

                                                                                          "-   ..........     -
                    lS-YD MINIMUM SAFE DISTANCE

      Figure 143. Arming and placement 'of foxhole digger explosive kit for damage.
170                            ,                                                                                        .                  .
                                                                                                                                               AGO 7258A
                                    G. CUTTING CABLE

                          FUZE SLEEVE
                                         MATING      TERMINAL~.

                                                      It         1>                  )]0 )               )

                                    PI. CONNECT   THE TWO SECTIONS OF CRATERING   CHARGE   AND
                                         ATTACH FUZE TO IT BY PUSHING FUZE SLEEVE OVER MATING

                                                             kCOTT.    ER PIN

                           SAFETY SLEEVE~                    Y
                              FIRING      BUTTO-N-Z-_@_LlI               __
                                                                      U_~_)     IJ:====:=-=-=--=--=
                                                                                       \STEEL    CABLE
                                  (2). REMOVE  PAPER FROM ONE SIDE OF ADHESIVE  TAPE AND
                                       FASTEN CRATERING  CHARGE TO TARGET ,IN THIS CASE A STEEL
                                       ROD OR CABLE

                                 (3).    HOLD     PLASTIC    PART OF FUZE WITH     LEFT HAND,   REMOVE       COTTER
                                         PIN AND SAFETY SLEEVE WITH RIGHT HAND,AND    PUSH FIRING
                                         BUTTON WITH THUMB. AFTER BUTTON IS PUSHED, PLASTIC PART
                                         OF FUZE MAY POP OFF AFTER ACTUATION  ;BUT THIS IS NOT

                                 (41. DURING        THE 20-SECOND    DELAY TlME,PROCEED TO A
                                         DISTANCE     OF AT LEAST 15YDS AND HOLD HANDS OVER                  EARS
                                         CAUTION:   AFTER PUSHING        BUTTON,DO    NOT TOUCH METAL PART
                                         OF FUZE. IT HEATS RAPIDLY       AND MAY     BE HOT ENOUGH
                                         TO BURN YOU

                                 H. FOR       OTHER TARGETS,SUCH     AS FLAT
                                        STEEL ,MOTORBLOCKS,AUTO                                          o
                                        TRANSMISSIONS     OR DIFFERENTIALS,
                                        YOU MAY NEED TO REMOVE        THE                                o
                                        PAPER FROM BOTH SIDES OF THE                     o
                                        ADHESIVE   TAPE

                                        CAUTION   WHEN PLACED ON BRITTLE TARGETS,                        o
                                        FRAGMENTS   MAY BE PROJECTED  BEYOND
                                        THE 15-YD MINIMUM  SAFETY DISTANCE

                                                    Figure 143-Continued.

equipment. The cratering charge, also being a                         and in damaging equipment.       Under critical
high explosive (weighs 5.7 ounces) may be use-                        conditions, however, test shots should be made
ful in cutting sma}l metal bars, rods, and cables                     to ascertain the effectiveness of the shaped

AGO 7258A
charge and cratering   charge.                                  for damage, see figure 143.
  d. Arming and Placement.                                        Note.    As the delay period         of the fuze
      (1) For arming procedure and placement                    may vary    from     20 to 50 seconds between
          for cratering see figure 142.                         units, users should    consider     the. delay as 20
      (2) For arming procedure and placement                    seconds for safety    reasons.

                                 Section   II. EXPEDIENT DEMOLITIONS

3. Use of Expedient     Techniques
  These techniques are not presented as a re-
placement for the standard demolition methods
but for use by experienced blasters in special
projects.  Availability of trained men, time,
and material will generally determine their use.      PLASTIC                                        CAP
4. Shaped    Charges
  a. Description.    Shaped charges concentrate
                                                         CONE                                         TICKS TAPED
the energy of the explosion released on a small                                                      TO SIDE AS
area, making a tubular or linear fracture in the                                                     STANO-OFF
target.   Their versatility and simplicity make
them effective against many targets, especially
those made of concrete or those with armor
plating. Shaped charges may be improvised
 (fig. 144). Because of the many variables,               a~
such as explosive density, configuration, and
density of the cavity liner, consistent results are
impossible to obtain. Thus experiment, or
trial and error, is necessary to determine the
op"tJmum standoff distances .. Plastic explosive '
                                                           Figure    144. Improvised

                                                                                           shaped    charge.-
is best suited for this type of charge. Dyna-
mite and molten TNT, however, may be used
as an expedient.                                         (3) Height      of explosive in container ::::
                                                                2 X height of cone measured from the
    b. Preparation. Almost any kind of con-                     base of the cone to the top of the eX-
 tainer is usable (fig. 144). Bowls, funnels,                   plosive.
 cone-shaped glasses (champagne glasses with
 the stem removed), and copper, tin, or zinc may         (4) Point of detonation           =
                                                                                       exact top center
 be used as cavity liners; or wine bottles with a               of charge.   Cover cap, if any part of
 cone. in the bottom (champagne or cognac                       it is exposed or extends above the
 bottles) are excellent. If none of these is                    charge, with a small quantity of C4
 available, a reduced effect \, is obtained by                  explosive (fig. 144).
 cutting a cavity into a plastic explosive block.                  Note. The narrow necks of bottles or the
-Optimum shaped charge characteristics are-                     stems of glasses may be cut by wrapping
                                                                them with a piece of soft absorbent type
      (1) Angle of cavity = between 30° and                     twine or string soaked in gasoline and
          60° (most HEAT ammunition has a                       lighting it.   Two bands of adhesive t~pe,
          42° to 45° angle)                                     one on each side of' the twine or strIng,
                                                                will hold it firmly in plac~. The bottle or
      (2) Standoff distance   = 11j2 X diameter                 stem must be. turned continuously with the
          of cone.                                              neck up, to heat the glass uniformly. Also, ;
                                                                narrow, band of plastic explosive place

172                                                                                                        AGO 7258A
              around the neck and burned gives the same
              result.   After the twine or plastic has
              burned, submerge the neck of the bottle in
              water and tap it against some object to
              break it off. Tape the sharp edge of the
              bottle to prevent cutting hands while tamp-
              ing the explosive in place.

 5. Opposed (Counterforce) Charge
   This technique is very effective against com-
paratively small cubical concrete and masonry
 objects 4 feet or less in thickness.  If properly
constructed of plastic explosive, placed, and
detonated, counterforce charges produce ex-
cellent results with a relatively small amount                             Figure   146.   Platter   charge.
of explosive. Their effectiveness results from                        \.

the simultaneous detonation of two charges                  of the target so that the charges may be placed
placed directly opposite each other and as near             flush against the respective target sides ..
the center of the target as possible (fig. 145).              c. Priming. The simultaneous explosion of
   a. Charge Calculation. The size is computed              both charges is mandatory for optimum results.
from the diameter or thickness of the target in             Crimp    nonelectric blasting caps to equal
feet, as-                                                   lengths   of detonating      cord. Prime      both
      The amount of explosive = 11/2 X the                  charges at the center rear point; then form a
      thickness of the target in feet (1112 pounds          V with the free ends of the detonating cord and
      per foot).                                            attach an electric or nonelectric means of firing.
Fractional measurements are rounded off to
the next higher foot prior to multiplication.               6. Platter Charge
For example, a concrete target measuring 3 feet                This device produces the Miznay-Chardin
9 inches thick requires llh X 4              =
                                      6. pounds of          effect. It turns a metal 'plate into a powerful
plastic explosive.                                          blunt-nosed projectile (fig. 146). The' platter
                                                            should be steel (preferably round, butsquare is
                                                            satisfactory)   and should weigh from 2 to 6
                                                               a. Calculations. Weight of explosive     ap-    =
                                                            proximately the weight of the platter.
                                                              b. Preparation.
                                                                 (1) Pack the explosive uniformly behind
                                                                      the platter. A container is not neces-

                                                    my                sary if the explosive can be held firmly
                                                                      against the platter.
                                                                                                Tape is ac-

                                                                 (2) Prime the charge from the exact rear
                                      ~                               center. Cover cap, if any part is ex-
                                                                      posE;d, with a small quantity of C4
                                                                      explosive to insure detonation.
               Figure   145.   Opposed    charge.
                                                                 (3) Aim the charge at the direct center
   d. Preparation and Emplacement. Divide                             of the target.
the calculated amount of explosive in half to                 c. Effect. The effective range (primarily a
make two identical charges. The two charges                 problem of aim) is approximately 35 yards for
must be placed diametrically opposite each                  a small target.    With practice, a demolitionist
other. This requires accessibility to both sides            may hit a 55-gallon' drum, a relatively small

AGO   7258A                                                                                                        173
 target,     at 25 yards about 90 percent              of the
                                                                 an inclosed space, like a box car or a warehouse
                                                                 or other relatively windowless structure.     At
 7. Grapeshot           Charge         (Improvised               detonation, the surround is distributed through-
    Claymore)                                                    out the air within the target and ignited by
                                                                 the incendiary material.
    This charge consists of a container, pref-
 erablya No. 10 can, projectiles (small pieces of
                                                                    a. Computation.
 steel), buffer material, an explosive charge, and                      (1) Charge size == 1 pound Ph explosive,
 a blasting cap. These are assembled as shown                               lh incendiary mix).
 in figure 147.                                                         (2) Cover size == 3 to 5 pounds for each
                                                                            1,000 cubic feet of target.   The one-
                                                                            pound charge will effectively detonate
           EXPLOSIVE    BUFFER
                                                                            up to 40 pounds of cover.
                                                                     b. Preparation. Powdered TNT may be ob-
                                                                  tained by crushing it in a canvas bag. The
                                                                 incendiary mix must be thoroughly dispersed
                                                                 throughout the explosive. A great number of
                                                                 dust materials may be used as cover, among
                                                                 which are coal dust, cocoa, bulk powdered
                                                                 coffee, confectioners sugar, tapioca, wheat flour,
                                                                 corn starch, hard rubber dust, aluminum
                                                                 powder, magnesi um powder, and powdered
                                                                 soap. If gasoline is used, 3 gallons is the
      REAR CENTER                SHRAPNEL
         PRIMING                                                 maximum, as more will not disperse evenly in
                                                                 the air and thus give poor results.
               Figure   1J,.7.   Grapeshot   charge.
                                                                 9. Improvised Cratering Charge
   a. Computation.   The weight of the explo-                        This charge is a mixture of ammonium
sive is approximately lit X the weight of the                    nitrate fertilizer containing at least 33 1/3 per-
                                                                 cent nitrogen and diesel fuel, motor oil, or gaso-
   b. Preparation.                                               line at a ratio of 25 pounds of fertilizer to a
      (1) Assemble the projectiles, a few inches                 quart of fuel. The fertilizer must not be
           of buffer material-earth,         leaves,             damp. From this mixture, improvised charges
            wood, felt, cloth, cardboard, etc., and             of almost any size or configuration can be made.
           the explosive charge. This should be                     a. Pour the liquid on the fertilizer.
            C4, packed firmly.                                      b. Allow the mixture to soal{ for an hour.
      (2) Prime the charge from the exact rear                      c. Place about half the charge in the borehole.
           center. Cover the cap, if any part is                Then place the primer, a primed I-pound block
           exposed, with a small quantity of C4                 of TNT, and add the renlainder of the charge.
           to insure. detonation.                               Never leave the charge in the borehole for a
      ( 3) Aim the charge toward the center of
                                                                long period, as accumulated moisture reduce~
           the target.                                          its effectiveness.
8. Dust Initiator                                                   d. Detonate the charge.

   This device consists of an explosive charge                   10. Ammonium Nitrate Satchel Charge
 (~owd~red T~T or C3; C4 will not properly
                                                                   While the cratering charge (para 9 above)
mIX WIth the Incendiary), an incendiary mix
                                                                is excellent, it is suitable only for cratering. A
 (2 parts of aluminum powder or magnesium
                                                                more manageable charge maybe used by mixing
pO,"'der to 3 parts of ferric oxide), and a
                                                                ammonium nitrate fertilizer with melted wax
sUItable finelY-divided organic material (dust)
                                                                instead of oil. The primer is set in place be-
or a volatile fuel such as gasoline called a sur-
                                                                fore the mixture hardens.
round. The dust initiator is most effective in
                                                                  a. Preparation.
                                                                                                         AGO 7258A
               (1) Melt ordinary paraffin and stir in                 Shrapnel material may be added to
                   ammonium nitrate pellets, making                   the mixture if desired or attached on
                   sure that the paraffin is hot while                the outside of the container to give a
                   mixing.                                            shrapnel effect.
              (2) Before the mixture hardens add a             b. Use. Because the wax and fertilizer may
                   half-pound block of TNT or its equiva-   be molded into almost any size or shape, it may
                   lent as a primer.                        be applied to a great many demolition projects
              (3) Pour the mixture into a container.        with satisfactory effects.

  ~ 1. Introduction          .                                   Coal dust
   , This section deals with materials usable in                 Cocoa
  the manufacture of homemade explosives, in-                   Powdered coffee
 cendiaries, and delay devices. Below is a                      Confectioners sugar
 partial list of commodities obtainable commer-                 Tapioca
 cially that may be used. A glance at this list                 Wheat flour
 will show the great complexity of the problem                  Powdered rice
 of security forces who must deny these to                      Cornstarch
 insurgents.    The strictest possible control of               Hard rubber dust
 their purchase and sale is imperative at the                   Cork dust
 earliest possible moment.                                      Powdered soap
  12. Commodity List                                            Photoflash powder
    The list is as follows:                                     Picric acid (certain dye derivatives)
      Ammonium nitrate (fertilizer)                             Phenol
      Ammonium perchlorate                                     Potassium permanganate
       Charcoal                                                Potassium nitrate
      Coal                                                     Potassium chlorate
      Common match heads                                       Powdered aluminum
      Calcium carbide                                          Powdered magnesium
      Catechol                                                 Powdered zinc
      Dinitrobenzine                                           Paraffin
      "Duco" cement                                            Petroleum jelly
      Flake aluminum                                           Pitch
      Fuel oil                                                 Rosin
      Glycerin                                                 Resorcinol
      Hydrogen peroxide (10 volume or higher)                 Red phosphorous
     Kerosene                                                  Sodi urn ni tra te
     Limed rosin                                              Sulfur
     Liquid floor wax                                         Sulfuric acid
     Lead dioxide                                             Stearic acid
     Lead tetraethyl                                          White phosphorous
     Manganese dioxide                                        Nitric acid
     Mercury or mercury salts                                 Calcium hypochlorite
     Nitrobenzine                                             Turpentine
     Nitromethane                                             Potassi urn dichromate
     Nitrocellulose (pyroxylin)                               Sodium peroxide
     Sodium chlorate                                          Nitric acid
     Sugar                                                    Copper sulfate
     Sawdust                                                  Carbon disulfide
AGO   7258A
        Plaster of Paris                                                   Nate. As a rule, improvised explosives and incendi-
        Ferric oxide                                                    aries are more dangerous to handle than conventional
        Barium peroxide                                                 explosives. Many mixtures may be ignited or detonated
        Red lead                                                        by a single spark, excessive heat, water, or the friction
                                                                        generated by stirring or mixing the ingredients         to-
        Ferric sulfate
                                                                        gether. Thus, only those who are well informed on the
        Aluminum powder                                                 characteristics and reactions of the ingredients should
        Aluminum sulfate                                                attempt to make improvised explosives.
        Silver nitrate powder

                                           Section IV.     UNDERWATER DEMOLITIONS
 13. Introduction
                                                                        14. Priming Underwater              Charges
     Underwater demolitions involve four basic                            a. Explosive.
 procedures-reconnaissance      in search of ob-
 stacles, charge priming, charge placement, and                                    (1) Types.     Tetrytol (M1 chain and M2
 charge initiation.                                                                     blocks), Composition C-3 (M3 and M5
    a. Reconnaissance.    As a map may show                                             blocks) , TNT, and bangalore tor-
 only the superficial character of a water ob-                                          pedoes are adaptable to underwater
 stacle, the important information must be ob-                                          demolitions.    Tetrytol may be sub-
 tained by on-site physical reconnaissance by                                          merged in water as long as 24 hours
 men trained in underwater techniques.                                                 without any appreciable effects on its
    b. Types of Obstacles. -Two types of obstacles                                     explosive characteristics, while C3 and
 may be found under water-natural        and arti-                                     TNT may be submerged longer if they
 ficial. Natural obstacles include steep banks,                                        remain. in the original package or are
 debris, floating logs and brush, underwater                                           placed in some other sort of container.
ledges, natural craters (particularly at ford                                          In addition two U. S. Navy charge
sites), rocks, shoals, sandbars, islands, icecrust,                                    assemblies-Mk       133 models 0 and 2
and floating ice. Artificial obstacles consist of                                      and Mk 135 model O-are           recom-
land mines, booby traps, floating mines, mines                                         mended for use under water.        They
attached to submerged poles, floating obstacles,                                       should not be submerged longer than
craters, concrete walls, barbed wire, and con-                                         3 hours before firing, however.
ventional concrete and metal obstacles generally                                (2) Mk 133 model 2 demoli,tioh charge as-
found on land but often very effective under                                        sembly.
                                                                                    (a) Characteristics     (fig. 148).
Mk 2 model 0 canvas haversack with waterproof,              fire-
                                                                                                 Size                     Weight    -
                                                                                           10 x 12 x 9 in                 23.5 lb
 proof and mildew-resistant  treatment.

      Main    charge
                                                                     Accessories                            . Remarks               -
                                                         10 ft of sash cord with 2 flat        Resembles Ml chain demolition
8 blocks H BX-1, 2.5           50/50 pentolite             hooks for lashing to obstacle;        charge. Five-foot length of de;
  lb each, strung 1 ft           located at center         flotation bladder for towing;
  a part on det cord.                                                                            cord extends from each end 0
                                 of block.                 and tow ring.

             (b) Use. The assembly is a source

                                                                                        detonating cord chain.
                 of eight    individual   demolition
                 charges-for   placing singly or as
                 multiple charges-by    cutting the

                                                                                                                           AGO 7258A





                            Figure   14-8.   U. S. Navy demolition charge assemblies.

         (3) Mk 135 Model 0 demolition charge as-                   (b)   Use. The     individual   explosive
                                                                          charge, being tightly wrapped in a
            (a) Characteristics (fig. 148).                               canvas bag, cannot be molded into
AGO    7258A
 323-561 0 - 68 - 12
                               Container                                     Color                   Size                     Weight
  Mk 3 model 0 haversack with waterproof,               fireproof,           Qray.            12 x 14 x 9 in               24 lb (approx)
   and mildew-resistant treatment.
               Main   Charge                                                                                 Accessories
                                                          Booster    (reinforce)
  10 blocks composition C3 (Mk 20               5-ft length of reinforced det cord,
    model 0), 2-lb each, in individual                                                       Each charge has a 3.5-ft sash cord and
                                                  looped to make a I-ft booster                flat hook for lashing to obstacle.
    canvas charge bags.                            core, molded into explosive block.          Haversack has a 10-ft sash cord and
                                                                                               2 flat hooks for lashing to obstacle,
                                                                                               a flotation bladder for towing by
                                                                                               swimmer, and a tow ring.
 Remarks.   Each charge has an ll-ft length of reinforced                   detonating   cord-5   ft is looped and molded in the block
   and the remaining 6 ft is an explosive lead.

             any desired shape, but it can be                              in paragraph 70b through d.
             bent or curved into close contact                                c. The following procedures should be fol-
             with the surface of the target.
                                                                           lowed, if possible, in underwater demolitions.
   b. Priming. Because detonating cord, though
                                                                           Charges should be placed so that-
 watersoaked, may be detonated if initiated at a
                                                                                 (1) Their pressure waves will not counter-"
 dry end, it is the most satisfactory of all firing
 systems for priming explosive charges used on                                         act each other. To avoid this, charges
 underwater obstacles. M1 chain, M2, M3, M5,                                           are placed in staggered lines-the
 M5A1, Ml12, and TNT blocks are primed by                                             adj acent charges containing different
 detonating cord as described in paragraphs 64                                        amounts of explosive. For example,
and 65. Bangalore torp~do sections are primed                                         if the first charge is 20 pounds, the
as described in paragraph 69b. Although the                                           second shouldbe 10 pounds, the third,
M1 chain demolition block may be primed by                                            20 pounds and so on.
means of a branch line attached to the deto-                                     (2) Their fragments will not be thrown
nating cord chain, priming is more positive if                                        toward friendly troops and equipment.
the detonating cord primer is wrapped and tied                                  (3) They will not throw heavy debris in
around the end of the block over the booster.                                         or partially obstruct a path to be taken
The same is true of priming the M2 block. The                                         by friendly troops or equipment.
2.5-lb. block of the Mk 133 model 0 assembly                                          For example, a charge placed on top of
should be primed by wrapping and tying the                                           a boulder may merely leave the large
detonating cord around the center over the                                           fragments that remain as obstruc-
booster; while the M3, M5, M5A1, Ml12, and                                           tions, and a charge placed directly un-
TNT, having no boosters, may be primed any-                                          der a boulder may form a few large
where on the block (para' 64).                                                       fragments and a large crater under-
15. Charge Placement                                                                 neath, thus enlarging instead of re-
    a. In underwater demolitions both single and                                     moving the obstacle. On the other
 multiple charges are used, depending on the                                         hand, a snakehole charge properly
 size and configuration of the target. The size                                      placed may move the boulder and frag-
 of the. charge is computed by the applicable                                        ments from the path. These prin,,:
 table or formula, but because of the tamping.                                       ciples also apply to the removal of
 effect of the water, charges on underwater                                         other obstacles.
targets require only about 1/3 as much explo-                            16. Charge Initiation
sive. as untamped charges used on similar
                                                                           Detonating cord systems used underwater
targets on land. Water-tamped charges, how-
                                                                        may be initiated by an electric or nonelectric
ever, require the same amount of explosive as
                                                                        detonating assembly attached to a dry end of
tamped charges on land.
                                                                        the ring main by means of a square knot (para
   b. Multiple charges are connected by deto-
                                                                        70a, fig. 85)" or by means of an electric or non-
nating cord branch lines .attached by means of
                                                                        electric firing system attached directly to the
knots to a main line or a ring main as described                        ring main.
178                                                                                                                           AGO 7258A

                                              Paragraph       Page
   Abatis --------------_______________           79                                                                       Paragraph     Page
                                                                   86     Batteries and dry cells                           App E
   Abutments:                                                                                                                                162
                                                                          Battery, silver chloride                          36                29
       Bridge --- ----------                      107a(1),    124,        Blasting caps:
                                                     109a     125              Characteristics                              App E
      Demolition formula --                       109a                                                                                    162
                                                               125             Commercial:
  Adapters, priming ------                        32              25
  Adhesive paste, M1 ----                         33                               Electric:
                                                                  25              Delay -----_______________               31, 31a
  Advanced demolition techniques:                                                                                                            25
                                                                                  Instantaneous  --                        31i31a            25
     -Counterforce charge (opposed)       __ App       F       66                 Noneelectric      -                      3Ib
      Dust initiator ------                  App       F                                                                                     25
                                                               66             Military:
      Foxhole digger ------                  App       F       66
      Grape shot charge -----                App       F                          Electric:
      Improvised cratering charge            App       F                               Delay __ --:_~                      31, 31a        25
      Improvised explosives                  App       F                               Instantaneous      _~               31, 31a        25
     Platter charge ------                   App       F                          Nonelectric                              31b            25
                                                               66        Blasting ice --                                   91e
      Satchel charge, ammonium                                                                                                           104
        nitrate   ----------                  App F                      Blasting kits. (See Kits, blasting.)
     Shaped charge, improvised                App F            66        Blasting machines:
     Square charge ----                       App F                           Fifty-cap  ----                              37c               31
 Aerial bombs:                                                                One hundred-cap                              37c               31
       Explosive content ---                  App C                           Ten-cap ----                                 37a
                                                              157                                                                            31
       Priming ------                         App C                           Thirty-cap                                   37b               31
       Use ----------_~                       App C                      Blasting permafrost                               91d           103
 Airfield destruction:                                                   Blockholing method _~                             97c           106
       Aircraft -------_______________        125e                       Bombs. (See Aerial bombs.)
       Plans ---------       '-              125a                        Boreholes:
       Priorities----=---                    125b            144
                                                                              Breaching charges                            86b            97
       Runways and taxiways                  125c                             Demolition of abutments                      109a(1)      125,
       Turf surfaces and pavements           125d            145                                                             and (2)    126
Amatol ----------_________________           14                              Drilling and enlarging                        88b (2)      100
Ammonia dynamite -_______________            19                              Road crate ring                            -- 89a, 90a     101
Ammonia-gelatin        dynamite              19b                             Timber-cutting                                78c           86
Ammonium nitrate -                           21                         Boulders, blasting:
Angled cratering method                -'~   91b             103            Blockholing                   ~               97c           106
Antitank ditch. (See Ditch,                                                 Mudcapping                                    97b           106
  antitank.)                                                                Snakeholing                        -----_     97a           106
Arch spans, components                       116a                       Breaching charges:
Artillery shells ----                        App C                          Breaching radius          ~                   86b
                                                             157                                                                         97
 Assemblies detonating cord:                                                Formula:
.    Electric ---------                      70a(2)                             Metric                                    App B
                                                              76                                                                        154
     Nonelectric    ------                   70a (1)          76                Summary                                   App D         160
Assembly, demolition charge, M37             25               16            Material factor K                             86c            99
Assembly, priming, M15                       25                             Number of charge"s                            87b
                                                              16                                                                         99
Atomic demolitions --                        104                            Tamping factor C                              86d
                                                             122                                                                         99
Authority, demolition of equipment
                                                                        Bridge demolitions:
  and supplies -----_______________          133a
                                                             147            Abutments ---                                 107a (1),    124,
Auger, earth -------                         40r(3)          48
Auger, posthole ---'-      ~                 40r(1)                                                                         109        125
                                                             48             Arch spans:
Bangalore torpedo:                                                              Components                               1I6a
    M1A1, MIA2 ----                          24a                                                                                       132
                                                             15                 Crown charges                            116c          133
    Rocket-propelled (Barney
                                                                                Filled spandrel arch                     116b          132
      Google) --- --                         26              16                 Haunch charges                           116d          133
AGO 7258A
                                                 Paragraph       Page
   Bridge demolitions-Continued                                                                                        Paragraph             Page
        Bailey bridges --                           120                 Charges:
                                                                  141        Bangalore    torpedo:
        Cantilever bridges, concrete:
             Without suspended span                 U3e                           M1A1, M1A2 ------.                       24                       15
             With suspended span                    113b                          Rocket-propelled     (Barney
                                                                  130               Google) ----.---                       26
        Cantilever truss bridges:                                                                                                                   16
                                                                            Breaching     --------                         86, 87       97,99
             Without suspended span                 U5e           131       Counterforce     (Opposed)       .__           App F           166
             With suspended span                    U5b           131       Cratering:
       Extent of demolition:
                                                                                 Ammonium nitrate                      21, 88a          12,99
            Complete -----                        106a            123
            Deliberate  ----                      103b                           Formulas, summary                     App D               160
                                                                  122            Foxhole digger -___________           App F
           Hasty ---------                        103e, 108b                                                                              166
                                                                 122,            Improvised ----                       App F
                                                                 125             Nitramon     ----                     22, 88a
            Partial   ------_____________         106b                                                                                  13,99
                                                                 123              Priming:
       Floating bridges:
            Pneumatic      floats -              119a                                  Detonating  cord            _    64-70                       72
                                                                 140                   Electric                    _
            Rigid pontons ----_________          119b                                                                   53-58                       63
                                                                 140                   Nonelectric               .__
            Treadways      ----                  11ge                                                                  44-49                  55
                                                                 140       Crown charges                           _
       Intermediate    supports:                                                                                       116e                  133
                                                                           Demolition charge M118                  _   11                           8
            External    charges ----             109b (2)        128       Demolition charge assembly,         M37     25                    16
                                                     (b)                   Dust initiator                          _
            Formula     ----                     109b(2)                                                               App F                166
                                                                 127       Grape shot charge                       _
            Internal   charges                   109b (2)                                                              App F                166
                                                                 128       Haunch charges                          _
                                                     (a)                                                               U6d                  133
                                                                           Platter    charge                       _
           Tamping     -----       .             109b (2)                                                              App F                166
                                                                           Pressure   charge:
      Open spandrel arch bridges:                                               Formula:
            Concrete ------                     117a                                Tamped                             84a                      95
            Steel arch span --                  117b                                Un tamped                          84b                      95
      Planning     -------                      108                       Projected    charges, demolitions
      Slab bridges ------                       111                          kits:
      Stringer bridges:                                                         Bangalore, rocket-propelled       _ 26                       16
            Continuous span ---               ._ l1o.e                          M1 and M1E1 --                      27a
           Simple span ---                       110b
                                                                128                                                                          17
                                                                128             M2, M2Al, M3, M3A1                  27b                      18
      Substructure      ----                     107a                           M157 --------                       27e
                                                                123                                                                          21
      Superstructure       ----____________      107b                     Satchel charge --                         App F
      Suspension spans --                        118
                                                                124                                                                         166
                                                                137        Shaped charges:
      T-beam bridges, concrete                   112
     Truss bridges ----                          114
                                                                129            M2A3 and M2A4                           23a                   14
Buildings, destruction              .            129
                                                                130            M3 --------.--                          23b                   14
                                                                146             Improvised --                          App F                166
C, tamping factor                               86d
Cables, suspension bridges,
  demolition of --------                        118b (4)
                                                                 99       Springing     charges _-'-
                                                                          Square charge -
                                                                                                                       App F
                                                                140       Steel-cutting    charges:
Calculation, electric circuit                   App E
                                                                162            Calculation formula                    81b                    89
Canals, demolition of                           124d                                                                                                1
                                                                144            Charge dimensions (ribbon)             80b                    88/
     Dry cell battery                          App E                           Other steels --         ~              81b(2)                89
                                                                162            Placement:                                                       j
     Power sources                             App E
                                                                162                 BUilt-up members             _                          91
     Storage battery                           App E                                                                  82d
                                                                162                 Irregular   steel shapes    __                          91
Cap crimpers:                                                                                                         82e
     Method of using                           35                                   Precautions                  _    82g                   92
                                                                 29                 Railroad rails               _                          89,
Caps. (See Blasting caps.)                                                                                            81b(3),
Cap sealing compound                           34                                                                       82e                 91
                                                                 29                Rods, chains, and cables                                 91
Card, demolition                               40p                                                                    82b
                                                                 47                "Rounding-off"    rule        _                          89
Ca uses, misfires:                                                                                                    81b(4)
     Detonating    cord system                 71                                  Steel members                 _    82e                   ~
                                                                 78                Steel sections                _
     Electric system                           61a-e                                                                  8~a, 83        91,92
                                                                 68                Structural  steel      ~      _                          89
     Nonelectric system                        50a,b                                                                  81b(1)
                                                             59, 60           Special techniques                 ._                         92
Channels, destruction     of                   124b                                                                   83
                                                                144           Types of steel __ ------           _                          89
Charge dimensions      (ribbon)                80b                                                                    81
                                                                88            Timber-cutting    charges                                     85
                                                 Paragraph       Page
   Circuits, electrical:                                                                                                   Paragraph      Page
                                                                                 Size of charge                                76b
        Resistance -----                          App E           162            Stemming                    ------            76e,
       Serie~ ------                              59a;                                                                                        84,
                                                                   65                                                            77a           85
                                                        App E     162            Tamping                              .        76e,
  Clip, detonating cord, M1                  _                                                                                                84,
                                                  39               33                                                             77b          85
  Combat equipment, demolition of            _    136             148            Underwater      (See Underwater
  Combination dual firing system             _    75                  80            demoli tions.)
  Commercial dynamite                        _    19                  10    Demolitions, bridge (See Bridge
  Communications systems, destruction             127,           145,         demolitions. )
    of      ---                              _
                                                    128           146       Demolitions, military                           8
  Composition B                              _                                                                                                 3
                                                  12                  9     Destructor, M10                                 40a               34
  Compositions C3 and C4                     _    9-10                 7    Destructor, M19                                 40b
  Complete demolition                        _                                                                                                34
                                                  106            123        Destruction of equipment and
  Computing tape                             _    400             45         supplies ---                                   133-135       147
  Construction    equipment,    demolition
    of                                       _                              Detonating cord:
                                               133-135           147            Connections, branch line                    70e,d
  Copper wire, firing                        _ 38a                                                                                            77
                                                                  32            Misfires                                    71
  Copper wire, resistance                    _ App E                                                                                          78
                                                                 162            Ring main                                   70d
  Counterforce  (opposed)      charge        _ App F                                                                                          77
                                                                 166            Type ----_____________________              30a
 Cratering:                                                                                                                                   28
                                                                            Detonating cord assemblies:
      Angled method                          _   91b             103            Electric --_____________________  70a (2)                     76
      Blasting ice                           _
                                                 91e             104            Nonelectric                       70a (1)                  76
      Blasting permafrost                    _   91d                        Detonating cord wick                  98b
                                                                 103                                                                      107
      Breaching holes                        _
                                                 88b(2)          100        Detonating velocity                   4a-d                      3
      Charge size and placement              _   88b              99        Detonation, premature                 62
      Culvert cratering                      _                                                                                             71
                                                 92              104        Detonators. (See Firing devices.)
     Deliberate method                       _   88b(1);                    Diamond charge --_________________ 83e
                                                                  99,                                                                     98
                                                    89a,b        101        Digger, foxhole              ,     -- App F                  166
      Hasty method                               90              101        Digger, post hole --                  40r(2)
      Ice conditions
                                                 91d(2) ,       103,       Ditch antitank:
                                                   e            104             Alinement and grade                        94b
     Relieved face crater                        91a                                                                                      105
                                                                102             Construction                               93a
     Stemming boreholes                          76e,                                                                                    105
                                                                 84,            Deliberate method                          93b
                                                                100             Electrical firing method                   94e (2)
     Surface charge                              91e(3)                                                                                  105
                                                                104             Hasty method -                             93e
     Type of explosive                           88a                                                                                     105
                                                                 99             Loading and firing charges                 94c
     Underwater   charges                        91e (4)                                                                                 105
                                                                104             Propagation method                         94e(l)        105
     Use of shaped charges                       91a,           102,            Test shots                                 94a           105
                                                   b,e           103       Driver, powder actuated                         40q
Crimper, cap -----                         35                                                                                             47
Current requirements, electric                                              Dual firing systems:
  blasting cap -----                    ' App E                                 Combination                               75              80
                                                                162             Detonating cord                           73
Deliberate demolitions                    103b                  122                                                                       79
Demolition card --                        40p                                   Electric                                  74              80
                                                                 47             Nonelectric                               73
Demolition charge assembly, M37           25                     16                                                                       79
                                                                            Dust initiator                                App F          166
Demolition kits:
                                                                           'Dynami te: .
     Antitank mineclearing                27                     17             Commercial:
     Bangalore, projected charge          26                     16                  Ammonia                  .______ 19a,b               10
     Earth rod, blasting                  41e                    50                  Gelatin                              19a,b           10
     Electric and nonelectric             41a,                   48
    Nonelectric    -----          .       41b                                       Straight       ~---------             19a,b           10
                                                                 50            Frozen                 ------------        199
Demolition orders ----___                 101,102                                                                                         11
                                                                109            Military                                   18              10
Demolitions:                                                                   Old                                        191            11
    Critical factors ---            .___ 76                      83             Priming of:
    Charge placement                     76d                     84                 Detonating cord .                     66             73
    Deliberate   ----________________    103b                   122                 Electric          ~                   56             65
    Hasty ------                         103e                   122                 Nonelectric                           47             55
    Nuclear weapons                      104                    122             Safe handling                             1ge,f          11
    Nuisance mining                      105                    123            ,Thawing kettle                            199            11
    Reserved ----                        103a                   122            Turning of cases                           1ge            11
AGO 7258A
                                              Paragraph            Page
   Earth auger                                    40r(3)              48
                                                                                                                               Parag-raph            Page
                                                                                 l\12Al, 8-second delay percus-
   Earth rod blasting kit                         41c                 50            sion detonator ----- __  .                     40/                    35
  Ednatol    --       .                            17
                                                                       9         M3 pull-release firing device                     40k                    43
  Effectiveness,  relative                        4d                   3         M5 pressure-release    firing device              40l                    43
  Electric and nonelectric blasting kit __        41a                 48         MI0 universal destructor          .               40a                    34
  Electric dual firing system                     74                  80         M19 destructor    ----                            40b                    34
  Electric firing system             -'-          51                 60
  Electric power formula                          App E             162     Firing    systems:
  Electric power plants, destruction of _         130               146          Detonating  cord:
  Electric wires, splicing                        52                 62              Advantages    of -                            63a                71
  End dam; bridge                                 107a(3)           124                Assembly:
  Explosives:                                                                               Advantages of --_____ __ 70a (4)                          76
      Amatol ---                               14                                           Attaching to system       70a(3)                          76
      Ammonium nitrate                         21                    12                     Electric    ---           70a (2)                         76
      Characteristics   of                  '_ 5                        4                   Nonelectric     --        70a (1)                         76
      Charge, demolition, M118                 11                       8              Clip --------______________    39                              33
      Composition     B                        12                                      Components     ---____________ 63b                             71
      Composition C3 (M3 and M5                                                        Connections:
         blocks) --                           9                                              Branch line                       70c
                                                                        7                                                                             77
         Composition C4 (M5Al and                                                            Detonating  cord                  70b                    76
           MU2 blocks)                        10a,b                                          Ring main                         70d
                                                                7,8                                                                                   77
        Definition                           4a
                                                                  3                    Misfires   -.---                        71                     78
        Destruction of                        145
                                                                152                    Priming:
        Detonating    velocity               4a
                                                                  3                         Bangalore      torpedo             69b
        Disposal of --_________________      145                                                                                                     74
                                                                152                         Cratering     charges              68
        Dynamite, commercial .               19                                                                                                      74
                                                                    10                     Dynamite                            66
        Dynamite,    military     ~          18                                                                                                      73
                                                                    10                        Ml chain demolition
        Ednatol '--.---__________________    17
                                                                     9                          block --                       65
        Foreign explosives                   20; App                                                                                                 73
                                                                11,                          M2, M3, M5, M5Al, and
                                                   C           157
       High .-------                         4c                                                 M12 demolition blocks         64a-c                  72
                                                                 3                           Plastic explosive        _
       Low ------____________________        4b                                                                               67                     73
                                                                 3                           Pole charges             _
       Nitramon    --     :..                22                                                                               69c                    76
                                                                 13                          Shaped charges           _
       Pentolite   ----_________________     16                                                                               69a                    74
                                                                    9                        TNT                      _
       PETN -----                            13                                                                               64a-c                  72
       RDX --------               -'-        15                                Dual firing systems:
       TNT ------                            7                                     Combination     --                         75                     80
      Tetrytol:                                                                    Detonating   cord                          73                     79
                                                                                   Electric                                   74                     80
           Ml chain demolition    block __ 8a                     4
           M2 demolition block             8b                                      Nonelectric                                73                     79
     Transportation     ------     '-      141a,b              150            Electric firing system:
     Velocity, detonating                  4a                                      Assembly --                                51a                    61
Extent of demolition                       106                                     Blasting caps                              51b,d           61, 62
External    charges ------              ~_ 77,78d                                  Blasting machines                          51c,d              62
Factors:                                                                             Circuits:
     Material   K --------                  86c                                            Common series            '        59a                 65
     Relative   effectiveness               4d
                                                                                           Leapfrog      series       .:.
                                                                                                                        __   59b                 6?
     Tamping    C ------                    86d                                      Misfires    -----          '--          6la-c               68
                                                                                     Precautions      ----                   51d                 62
Firing devices:
                                                                                     Premature      detonation               62                  71
     Ml concussion detonator                40c
                                                               34                    Priming:
     Ml delay firing device                 40h
                                                               36                         Ammonium nitrate                   57                  65
     Ml pull firing device                  40j
                                                               42                         Bangalore torpedo                  58b                 65
     MIAI pressure firing device            40i                40                         Demolition b~ocks                  53, 55          63,65
     MIAl, 15-second delay friction
      detonator    --_________________      40d                                          Dynamite    __ ~                    56                  65
                                                               35                           Ml chain demolition               .
      MIA 2, I5-second  delay percus-
                                                                                               block ----       ~            54                 64
        SIOn detonator                   40e                   35                           MU8 demolition charge            58e                65
      M2, 8-second delay friction de-                                                       Nitramon    _.,.-                57
       tonator   ------               ._ 40g                  36                            Plastic, explosive               55b                65

182                                                                                                                                      AGO 7258A
                                                      Paragraph       Page
   Firing    systems-Continued                                                                                                   Paragraph      Page
                    Shaped charges                     58a
                                                                           65           Safety ---------            ~_________    29a
                    TNT ----                           53                                                                                            22
                                                                           63           Time, blasting ~700                       29b
              Splices:                                                                                                                               22
                                                                                   Fuse lighters:
                   "Pigtail" --                        52a
                                                                          63            ~2 ---------------                        401n
                   Protection of --                    52c                                                                                          45
                                                                          63           ~60 --------------____________             40n
              Testing of:                                                                                                                           45
                                                                                       ~atch -------------___________             43j               54
                   Cap                            _
                                                    51a                61          Galvanometer        -----------                36, 51a-c,       29,
                   Entire circuit                 _ 60;c               68                                                            60a-c         61,
                   Firing wires                   _
                                                    60a                67                                                                          67
                   Series circuits                _ 60b                68          Gelatin dynamite --------__________         19a.,b             10
                   Use of galvanometer            _ 51a-c;            61,          Grape shot charge ------                    App F
                                                      60a,c            67          Gun, ram-set -------_______________         40q
                     Wire connections            __ 51c                                                                                           47
                                                                         62        Handling detonating cord misfires __ 71                          78
       Nonelectric firing system:                                                  Handling electric misfires                  61
           Assembly ------                            43a-j                                                                                         68
                                                                       53          Handling nonelectric misfires               50
           Caps, blasting --                          31b                                                                                         59
                                                                       25          Hasty demolitions -----                     103c             '122
           Crimper, cap -----                         35                           Haunch charges -----______________          116d
                                                                      29                                                                        133
             Fuse:                                                                High-explosive    ----                      4c
                 Safety ---------                     29a             22           Highways, demolition of                     121
                  Time blasting 700                   29b             22          Ice, blasting in ----________________       91e
             Fuse lighters:                                                       Improvised cratering charge                 App F
                  ~2 -----------________ 40rn                         45
                                                                                  Induced currents ---_______________         62a
                  ~60 --------__________ 40n                          45          Initiator~ dust ------                      App F
                   ~atch -------                      43j                         InstaIiations,  demolition of               130-132
                                                                      54                                                                        146
             ~isfires   -------                       50a,b        59,60          Insurgency mixtures -                       App F
             Priming:                                                             Intermediate   supports, demolition of _ 109b                 127
                   Ammonium nitrate              _ 48                             K, material factor -                 :...__ 86c
                                                                      58                                                                           99
                   Bangalore torpedo             _ 49b                            Kits, demolition. (See Demolition
                                                                      59            kits.)
                   Demolition blocks             _ 44a,b,c            55
                  Dynamite                       _                                Land mines:
                                                   47ar-c             56
                  ~1 chain demolition                                                 Priming ---------                       App C
                    block                    _                                                                                                 157
                                                   45                 55               Safety in use -----                    App C
                . ~118 demolition charge     _
                                                  49c                 59               U. S. and foreign -                    App C
                  Nitramon                   _                                                                                                 157
                                                  48                  58         Lateral root stumps, blasting                96b
                  Shaped charges             _                                                                                                 106
                                                  49a                 58         Lighter, fuse ~2 ---_______________          40rn
                  TNT                        _                                                                                                  45
                                                  44a,b              55          Lighter fuse ~60 --               ~______    40n
                  Use of crimper             _                                                                                                  45
                                                  43e-g              54          Lightning, premature explosion
 Firing wire:                                                                      effects --------__________________         62b
      Testing of -------_____________  60a                                                                                                      71
                                                                     67          Lines of transportation,   demolition of     121-126          141
      Types ------------------------_38a                             32          Low explosives                               4b
 Firing wire and reel ----___________  38a,b                                                                                                       3
                                                                  32,33          ~achines, blasting. (See Blasting
 Fixed bridges, components             107                                         machines.)
 Floating bridges, demolition of       119a-c
                                                                    140          ~agazines:
 Foreign    explosives   ---                      20; App
                                                                     11,             Field expedient                         143               151
                                                       C            157              Lightning protection                    142d
 Formulas:                                                                                                                                     151
     Summary of:                                                                     Safe distance and formula               139               149
                                                                                     Safety rules                            144               152
           Breaching charges                 _
                                                 App         D      160                Temporary storage in training
           Cratering charges                 _
                                                 App        D      160                   areas --           ~_____________   144
           Diamond charge                    _                                                                                                 152
                                                 App        D      160                Types ----____________________         142a
           Electric power                    _                                                                                                 151
                                                 App         E     162          ~aterial     factor K                        86c
           Pressure charges                  _                                                                                                 99
                                                 App        D      160          ~ateriel,    destruction of                  136
           Ribbon charge                     _                                                                                                 148
                                                 App        D      160          ~aximum        circuit capabilities of
           Saddle charge             _
                                                 App        D      160             various power sources                     App E
          Safe distance                      _                                                                                                162
                                                 App        D      160          ~etric calculation (all formulas)            App B
          Steel cutting                      _                                                                                                154
                                                 App        D      160          ~ilitary    dynamite                         18
          Timber cutting                     _                                                                                                 10
                                                 App        D      160          ~ines as demolition obstacles                105; App
Foxhole digger                               _                                                                                               123,
                                                 App        F      166
Frozen dynamite                          _                                                                                       C           157
                                                 199                11          ~ixtures,   explosive,   insurgency          App F           166
AGO 7258A

                                                     Paragraph         Page
    Misfires:                                                                                                                    Paragraph          Page
                                                                                          .Destruction and disposal,
         Detonating cord ----                         71                   78
        Electric                                     61a-c                                   explosive --------                  145                152
                                                                           68             Dynamite -~----------                 1ge, 1               11
        Nonelectric      ----                        50a,b                 59
   Mudcapping ----                                   97b                                  Field expedient magazines             143                 151
                                                                       106                Lightning protection                  142d                151
   Nonelectric demolition set                        41b                50                Magazines -------_____________        142-144             151
   Nuclear weapons demolitions .                     104               122                Minimum safe distance              ._ 139                 149
   Nuisance mining -               .                 105
                                                                       123                Misfires --------                     50a,b;
   Ohm's law ------                                  App E                                                                                   59,60,
                                                                       162                                                                       68,
   Old dynamite ------                               191                                                                         61a-c;
                                                                        11                                                                       78
   Open spandrel arch bridge                         117a                                                                        71
                                                                       134              Package care and repair                140                 150
   Opposed (counterforce)     charge                App F              166              Premature explosions                  62                    71
  Package charges -                              ._ 28a
                                                                       21              Responsibility  -                      138b                 149
  Partial demolition -                              106b
                                                                   123                 Safe distance formula                  139                  149
  Pavements, breaching of                      .,._ 88b (2)        100                 Transportation,   explosives           141                  150
  Pentolite    --------              .              16
                                                                     9            Satchel charge ---                          App F                166
  Permafrost,     blasting in                       91d
                                                                   103            Sealing compound, weatherproof              34
  PETN ------                                       13                                                                                              29
                                                                           9      Series circuits calculations                App E
  Petroleum facilities, demolition of                132                                                                                           162
                                                                   146            Sets, demolition:
  Pigtail (Western Union) splice                     52a               63
  Pipeline demolitions                               126                               Earth rod ----                         41c                  50
                                                                   145                 Electric and nonelectric               41a
  Plastic explosive:                                                                                                                               48
       C3 --------                                 9                                   Nonelectric  ----                      41b                  50
                                                                           7      Shaped charges:
       C4   --------                               10a"b
                                                                  7,8                 Improvised ----                        App F
  Platter charge ----                             App F                                                                                           166
                                                                  166                 M2A3 and M2A4                          23a
  Pneumatic floats, demolition of              .__119a                                                                                             14
                                                                   140                M3 ----.-----                          23b
 Pole charges ------          ~                   28b                                                                                              14
 Posthole auger --------                          40r(1)                         Simple span, demolition of:
 Posthole digger ----.--                          40r(2)                              Stringer bridge --                     110                  128
 Powder-actuated      driver                      40q                                T-beam bridge ---                       112                  129
 Power sources, capacity of                       App E                          Slab bridge, demolition of                  111                  129
 Premature explosions, lightning         and                                     Snakehole charge ----                       97a                  106
    RF currents --------                         62                              Splices, electrical wire:
 Pressure charges -----                          84                                   Methods ---------                    -' 52a,b .
                                                                   95                                                                              63
 Propagation method, ditching                    94c(1)                               Protection of --------__________        52c                  63
 Quarrying   --------                            99                                   Staggered     ---------                 52b
                                                                  10.7                                                                            63
 Radio frequency (RF) currents                   62a                             Springing charges ----                       98                 106
 Railroad demolitions:                                                           Square charge -----.-                        App F              166
      Roadbeds -------------                    122b                             Square knot, detonating cord
      Track --------------                      122a                               assembly --                              70a(3)                76
 Ram-set gun ------.                            40q                              Steel arch span bridge, demolition of      117b                 137
RDX -------                     .               15                               Steel, types ----_-'     .....             81a                   89
Reconnaissance                                  101b                             Steel cutting. (See also Charges,
Reel, firing wire:                                                                 steel-cutting. )
     500-foot --------                          38b (2)                               Charges ------                        81b                   89
     1000-foot --                               38b (3)                             Formulas:
     RL 39A ---------------                     38b (1)           33                    Metric --------                     App B                154
Relative effectiveness                          4d                                      Summary ----                        App D                160
Reserved demolitions                .           103a                            Stemming -----------.-                      76c,                 84,
Resistance, electrical                          App E                                                                                             85 .
                                                                 162                                                          77a
Ribbon charge                            .      83d                             Storage    battery,   power source          App E
                                                                  93                                                                         162
Rigid pontons                                  11gb
                                                                 140            Storage of explosives:
Rocket-propelled bangalore    .                26                                     Field expedients -----       ~       143
                                                                  16                                                                         151
"Rounding-off" rule                            81b (4)
                                                                  89                  Safety rules. (See also Safety
Runways and taxiways, demolition of            125c              145                    precautions.)  ---                  140, 141         150
Saddle charge -                                83b
                                                                  92            Straight dynamite ---        .__-:         .19                10
Safety fuse ----                               29a
                                                                  22            Stump blasting:
Safety precautions:
                                                                                    Lateral root stumps                    96b               106
     Blasting caps --                          141b(3)           150                Rule ofthumb                 __
                                                                                                               .:- .       96                106
     Compliance with -                         138a              149                Taproot stumps                         96a               106

184                                                                                                                                  AGO'l258A
                                                 Parag-raph     Pag-e
   Substructures,   bridge            _                                                                                    Paragraph         Page
                                          107a                      123      Tamping     ------    --                       76c; 77a,
   Superstructures,   bridge            _ 107b                                                                                                84,
                                                                    124                                                          b              85
   Supplementary demolition obstacles __ 105                        123     Tamping factor C --                             86d
   Suspension span bridge           _                                                                                                           99
                                          118                       137     Tamping materials                               77                85
    Tables:                                                                 Tape, computing          ~                     400                45
    Table I. Comparison of M2, M2A1,                                        Taxiways, demolition of                        125c              145
      M3 and M3A1 projected charge                                          Telephone and telegraph            systems,
      demolition kits                      _                                  demolition of -- -                     ~__ 127                 145
   Table II. Detonating cord data         _                         24      Tetrytol -- -- - --     -                    8                     4
   Table III. Electric blasting cap char-                                   Thawing kettle, dynamite                     199                  11
     acteristics                          _                                 Timber-cutting charges:
   Table IV. Nonelectric     blasting cap                                       Calculation -                              78a-c              85
     characteristics                      _                                     Formulas -----                             App B,
                                                                    29                                                                       154,
   Table V. Operating range of concus-                                                                                      D
     sion detonators                      _                                                                                                  160
                                                                    35           Placement of                            78d,e                86
  Table VI. Temperature     corrections                                    Time fuse, M700                               29b
    for M1 delay firing device          _                           39     TNT - -----                                   7                      4
  Table VII. Minimum safe        distance                                  Towers, suspension bridge, demoli-
    for RF transmitters                      _                               tion of -----                              118a(2)              137
  Table VIII. Characteristics     of   ex-                                 Transportation    lines, demolition of __ 121-126                 141
    plosives                                 _                             Transportation    of explosives __ ....      141                  150
  Table IX. TNT     needed to cut steel                                    Treadways, destruction of                    119c                 140
    sections                                 _                             Tunnels, demolition of                       123              142
 Table X. TNT required for tamped                                          Turf surfaces and pavements,            de-
   pressure charges                    _                                     struction of                               125d
                                                                96                                                                       145
 Table XI. Value of K (material fac-                                       Underwater demolitions                      App F             166
   tor) for breaching charges         _                                         Charge placement                       App F             166
 Table XII. Size of boreholes made by                                           Charge initiation               .      App F             166
   shaped charges                     _                                         Obstacles                              App F             166
 Table XIII.   Charge size for blasting                                         Priming explosive charges:
   boulders                                 _                                        Bangalore torpedo                 69b; App           74,
 Table XIV. Minimum safe distances                                                                                         F             166
   from explosives for persons in the                                                MK 133 model 2 demolition
   open _~_~         ~         ~      _                                               charge                           App F             166
                                                               149                  MK 135 model 0 demolition
 Table XV. Magazine locations (un-
   barricaded)                        _                                              charge                            App F             166
                                                               151                  M3                                 64; App
 Table XVI. Value of material factor                                                                                                      72,
   K for calculation  of breaching                                                                                       F               166
   (metri-c)                         _                                              M5                                 64; App            72,
                                                              154                                                        F
 Table XVII. Characteristics   of prin-                                                                                                 166
                                                                                   M5Al                             ._ 64; App           72,
   cipal U. S. explosives (metric)        .~__                155                                                        F              166
 Table XVIII. Steel cutting charges                                                M112                    .          64; App
   (metric)                             _                                                                                                72,
                                                              155                                                        F              166
Table XIX. Minimum safe distances                                                  Tetrytol,      M1 chain, M2        App F             166
    (in the open) (metric)         ---                        156                  TNT                                App F             166
Table XX. Explosive content of gen-                                        Vessels, destruction of                    124a
 . eral purpose bombs                  _                                                                                                144
                                                              158          Voltage drop, calculation of               App E             162
Table XI. Resistance of various sizes                                      Water supply, destruction of               131
   of copper wire                      _                                                                                                146
                                                              162         Water transportation     s~stems, dem-
Table XXII. Maximum circuit capa-                                            olition of                               124a-d            144
   cities of various power sources    _                       164         \-Vire, firing                              38                 32

AGO 7258A
       By Order of the Secretary of the Army:

                                                                         HAROLD K. JOHNSON,
Official:                                                                General,' United States Army,
                                                                         Chief of Staff .
  Major Gen'eral, United States Army,
  T he Adjutant General.

     To be distributed in accordance with DA Form 12-11 for Explosives and Demolition .

                                                                                                .       ..


                                                                                           I,       ,

                          U.S. GOVERNMENT   PRINTING   OFFICE:   1967-/7258A


Shared By: