Carruthers - German Tank Hunters: The Panzerjäger

The first weapon of the German Panzerjger ( armour hunters or tank hunters) was the humble Panzerbchse which was in service from 1917 through to 1943. Panzerbchse literally means "armour rifle" and German anti-tank rifles originated back in 1917 with the Mauser 1918 T-Gewehr, the world's first anti-tank rifle. It was created as an immediate response to the appearance of British tanks on the Western Front. A single shot manually operated rifle, it enjoyed moderate success, with approximately 15,800 rifles eventually produced. The Panzerbchse 39 (PzB 39) was the main German anti-tank rifle used in World War II. It was an improvement of the unsuccessful Panzerbchse 38 (PzB 38) rifle.

German Panzerbchse development resumed in the late 1930s. In an effort to provide infantry with a man-portable lightweight anti-tank rifle. The task fell to Dipl.-Ing. (certified engineer) B. Brauer at Gustloff Werke in Suhl who designed the Panzerbchse 38 (PzB 38). It was a manually loaded single-shot weapon with a recoiling barrel. When fired, the barrel recoiled about 9 cm, which opened the breech and ejected the spent cartridge casing. The breech block was then arrested in the rear position, remaining opened for the gunner to manually insert a new cartridge. The gunner then released the cocked breech with a lever at the grip. The breech and barrel would then move forward again and the trigger was cocked in preparation to fire. This rather complicated mechanism was prone to jamming as the system easily fouled in field use.

Although manufactured with pressed steel parts that were spot-welded, because of the complicated vertical breech block mechanism the Panzerbchse 38 was difficult to manufacture and only a small number of 1,408 PzB 38 rifles were built in 1939 and 1940 at the Gustloff Werke plant; only 62 of these weapons were used by German troops in the invasion of Poland in 1939.

The Panzerbchse 39 was the next development, and was found to be a major improvement as a result the Panzerbchse 38 declared obscelescent and production was immediately switched to the Panzerbchse 39. However it too featured a vertical breech block mechanism and used the same cartridge. It retained the barrel of the PzB 38 and had an only slightly increased overall length of 162.0 centimetres (63.8 in); weight was reduced to 12.6 kilograms (28 lb). Its performance data was basically the same as that of the PzB 38. To increase the practical rate of fire, two cartridge-holding cases containing 10 rounds each could be attached to both sides of the weapon near the breech - these were not magazines feeding the weapon, they simply enabled the loader to extract the cartridges (that he still had to manually insert into the gun) from the conveniently placed magazines. 568 PzB 39 were used by the German army in the invasion of Poland; two years later, at the beginning of the war against Russia, 25,298 PzB 39 were in use by German troops; total production from March 1940 to November 1941, when production ceased, was 39,232 rifles. The PzB 39 remained in use until 1944, by which time it had become hopelessly inadequate against all but the lightest armored vehicles.

OKW recognised the need for a more powerful form of anti-tank weapon and the design of a horse-drawn, 3.7 cm anti-tank gun (designated 3.7 cm Pak L/45) by Rheinmetall commenced in 1924 and the first guns were issued in 1928. However, by the early 1930s, it was apparent that horse-drawn artillery was obsolescent, and the gun was modified for motorized transport by substituting magnesium-alloy wheels with pneumatic tyres for the original spoked wooden wheels. Re-designated the 3.7 cm Pak 35/36, it began to replace the 3.7 Pak L/45 in 1934 and first appeared in combat in 1936 during the Spanish Civil War. It formed the basis for many other nations' anti-tank guns during the first years of World War II. The KwK 36 L/45 was the same gun but adapted as the main armament on several tanks, most notably the early models of the Panzer III.

The Pak 36, being a small-calibre weapon, was outdated by the May 1940 Western Campaign, and crews found them inadequate against allied tanks like the British Mk.II Matilda, and the French Char B1 and Somua S35. Still, the gun was effective against the most common light tanks, such as the Renault FT-17 and saw wide service during the Battle of France and the T-26 during Operation Barbarossa. The widespread introduction of medium tanks quickly erased the gun's effectiveness; miserable performance against the T-34 on the Eastern Front led to the Pak 36 being derisively dubbed the "Door Knocker" (Heeresanklopfgert, literally "army door-knocking device") for its inability to do anything other than advertise its presence to a T-34 by futilely bouncing rounds off its armor.