Kb ppanc wz.35 – Anti-Tank Rifle
WEAPON ROF DAM PEN BLK MAG SS/BRST RNG
8 to 10 round/min 12 2-4-9 8 4 4/- 75m
ROUND 7.92 x 107mm ”DS”
MAG 4 box magazine
WEIGHT 10 kg (loaded)
OTHER Muzzle velocity 1275 m/s 4180 f/s - Length:1760 Barrel length:1200mm
The karabin przeciwpancerny wzór 35 (kb ppanc wz.35, literally Anti-armour rifle Model 35), was a Polish 7.92 mm anti-tank rifle used by the
Polish Army during the Polish Defensive War of 1939. It was also known by its code name of kb Urugwaj (kb Ur) or by the name of its designer,
Since the weapon was initially one of the top secrets of the Polish Army, it was also known under many different code-names. Until the
mobilisation of 1939 the combat-ready rifles were held in closed crates marked with the enigmatic inscription "Do not open; surveillance
equipment". Among the cover names was Urugwaj (hence Ur) being the Polish name of Uruguay, the country to which the surveillance equipment
was supposedly exported). After the fall of Poland the German army captured large quantities of the kb ppanc wz.35 and used it as Panzerbüchse
35 (polnisch) (PzB 35(p)). The Italian army also benefitted from the booty and used it under its own designation of fucile controcarro 35(P). In both
cases the new name translating more or less as Anti-tank Rifle Number 35 Polish.
In appearance it resembles a rifle with a longer than normal barrel supported by a bipod at the front of the wooden stock. It is a bolt
action rifle, fed from a 4-round box magazine. The barrel is equipped with a muzzle brake for greater accuracy and to limit the recoil. The brake
absorbs approximately 65% of the shot energy and the recoil was comparable to the standard Mauser rifle, even though the cartridge carried
more than twice the amount of propellant. It has fitted iron sights fixed for 300 metres range.
In the late 1920s the Polish General Staff started the development of a light anti-tank weapon for the Polish infantry. In 1931 Lt. Colonel
Tadeusz Felsztyn from the Institute of Armament Technology in Warsaw started the first tests of various low-calibre cartridges. After the tests of
German-made Hagler bullets proved the possibilities of that type ammunition in perforating steel plate, the National Ammunition Factory in
Skarżysko-Kamienna was ordered to develop its own 7.92 mm cartridge with a muzzle velocity of over 1000 metres per second. After a series of
tests, the new DS cartridge was proposed.
The DS ammunition was based on a standard 7.92 mm bullet as used by both the Mauser rifle Model 1898 (wz.98) and its Polish variant the
karabinek wz.29. The length of the cartridge was extended to 131.2 mm and the overall weight was 64.25 g. After an additional series of tests the
copper cartridge case was replaced with a case made of brass (67% copper/ 23% zinc). Uniquely, compared to other armour-piercing designs, the
DS round instead of using tungsten or a similar hard metal for the core had lead in a steel coating, like ordinary rifle bullets. The penetration was
not through punching the core through the armour but from the impact of the bullet flattening against the plate, transferring kinetic energy to
the metal. The key to success for this technique was a very high bullet velocity. The result was that the bullet was punching a core, about 20 mm
in diameter out of the armour, a larger size than the actual rifle caliber.
Simultaneously to the development of the ammunition, a young graduate of the Warsaw University of Technology, Józef Maroszek was
ordered to prepare an anti-tank rifle. On August 1, 1935, the Committee of Equipment and Armament officially ordered the rifle and in October the
first tests of the new weapon started.
The rifle was based on the successful construction of the Mauser rifle, a standard pre-World War I infantry weapon. The gun-lock was modified to
sustain higher pressure of the new cartridge and the barrel was extended significantly. The first tests carried out in Brześć and Pionki showed
that the new weapon was capable of perforating a 15 mm steel plate from the distance of 300 metres. Similar results were reached after firing at
a deflected steel plate. Initially the new muzzle could only sustain up to 30 shots, after which it had to be replaced with a new one. However, this
drawback was soon corrected and the final prototype could fire approximately 300 shots. The committee accepted the new design on November
25, 1935, and in December the Ministry of Military Affairs ordered the delivery of 5 rifles, 5000 bullets and a set of spare muzzles for further tests.
After the tests carried out by the Centre of Infantry Training in Rembertów proved high effectiveness and reliability of kbk ppanc wz.35, the
Ministry ordered 7610 rifles to be delivered to the Polish Army by the end of 1939. It is uncertain how many rifles were actually produced, but it is
often estimated that there were more than 6500 pieces delivered by September 1939.
The rifle was the main anti-tank weapon of an infantry platoon. Each infantry company and cavalry squadron was to be equipped with
three rifles, each operated by a team of two soldiers. Additional anti-tank teams were to be created at a later stage. Although the weapon was
successively introduced to the units, it remained a top secret. The rifles were kept in closed wooden crates, each marked with a number and a
notice do not open; surveillance equipment. The teams were trained in secret military facilities just before the war, starting from July 1939, and
then had to give an oath that they will preserve the secret.
The rifle was carried by the leader of the two-man rifle team on a carrying strap. The other member of the squad was his aid and provided him
with cover while he was reloading. The weapon was usually fired from prone supported position with the bipod attached to the barrel. However,
it could be also used in other positions, like prone unsupported and crouch. The effective range was 300 metres and the weapon was effective
against all German tanks of the epoch (those being Panzer I, II and III, as well as Czech-made LT-35 and LT-38) at 100 metres. At up to 400 metres
it could destroy all lightly-armoured vehicles. It could penetrate 15 mm of armour, sloped at 30° at 300 m distance, or 33 mm of armour at 100 m.
What is interesting, an Italian manual stated maximum penetration as 40 mm.
Despite well-established opinion, the Karabin przeciwpancerny wz.35 was extensively used during the Polish Defensive War of 1939 by
most Polish units. After Poland was overrun by Germany and the Soviet Union, large quantities of this weapon were captured. The Germans
pressed it into service as Panzerbüchse 35 (polnisch) (PzB 35(p)), and sped up works upon their own simplified, one-shot anti-tank rifle
Panzerbüchse 39 (PzB 39). According to some sources, the Germans however replaced DS bullets in a captured ammunition with their own 7.92
mm bullets with a hardened steel core from the PzB 39. Also, several features of the Polish rifle, most notably a lock, were used in development
of the Soviet PTRD, 14.5 mm anti-tank rifle.
In 1940 Germany sold approximately 800 Polish rifles to the armed forces of Italy, who used it in combat until the end of World War II.