75 mm PaK-40 Anti-Tank Gun
In 1939 the German army issued a specification for a 75mm Anti-tank gun (Panzerabwehrkanone) to Krupp and Rheinmetal, but development was given a low priority until after the invasion of the Soviet Union in the summer of 1941 when the German Panzers began to encounter the superior T.34 and KV.1 tanks of the Red Army.
Hurriedly raced into production the first PaK-40s began to reach the front in November 1941 and soon proved to be an accurate and efficient tank killer. By 1943 it had become the principle antitank gun in service with the German army and most of its allies.
With an effective range of 1,000-1,500 yards, the PaK-40 could fire a 15-lb armour-piercing round at 2,598 feet per second, enabling it to penetrate up to 106 mm of steel at 500 yards. Later a 7-lb tungsten-cored round (AP40) was developed with a muzzle velocity of 3,060 feet metres which could punch through 115 mm of steel at 500 yards allowing it to take on virtually every Allied tank in production, with the exception of the Soviet IS-2 and American M.26 Pershing. With an experienced crew of eight the gun could fire up to 10 rounds per minute. In addition High Explosive and Hollow Charge (in small quantities) rounds were also available for the PaK-40
If the PaK-40 did have one drawback it was that of weight. At 3,350–lbs it was too heavy to be moved easily through mud, snow or rough terrain without the aid of an artillery tractor. Nevertheless, at the inspiration of Heinz Guderian, the gun (designated KwK-40)was successfully mounted on a number of Self-Propelled chassis such as the Panzerjager Marder III Tank Destroyer, SdKfz 234/4 Armoured Car and SdKfz 251 Halftrack, thus permitting more Anti-Tank guns to be made available counter the overwhelming numbers of Allied tanks making their appearance in the latter stages of the war.
After the war a number of other countries (including Albania, Bulgaria, Czechoslovakia, Hungary and Romania) continued to utilise war surplus PaK-40s within their armed forces for some years, until the advent of the modern antitank missile made such weapons virtually obsolete.