ShVAK

The ShVAK is a Soviet 20 mm autocannon used by the Soviet Air Force in World War II. It was designed by Boris Shpitalniy and Semyon Vladimirov in 1935-1936, based on an earlier 12.7 mm machine gun with which it shares its name. The ShVAK was mounted on many Soviet aircraft, such as the La-5, Yak-1, and MiG-3. It was also adapted for light tanks as the TNSh. The ShVAK used a gas-operated action and a belt-fed system, unlike some Allied contemporaries. It had a rate of fire of 700-850 rounds per minute and a muzzle velocity of 750-790 meters per second, firing 20×99mmR cartridges with high-explosive or armor-piercing shells. This was one of the most widely produced and effective Soviet autocannons of the war.