Almost from the moment of its official adoption by the Soviet military in 1949, the AK-47 was recognized as being simple to operate, rugged, reliable under trying conditions, and amenable to mass production. Built around a 7.62-mm round with a muzzle velocity of some 700 meters per second, it had a cyclic firing rate of 600 rounds per minute and was capable of both semiautomatic and automatic fire. A long curved box magazine held 30 rounds, and a separate gas-return tube above the barrel held a piston that was forced back upon firing to activate the mechanisms that ejected the spent cartridge and cocked the hammer for the next round. The AK-47 was manufactured in two basic designs, one with a wooden stock and the other, designated the AKS, with a folding metal stock. Beginning in 1959, the AK-47 was replaced in first-line Soviet service by the AKM, a modernized version fitted with longer-range sights and cheaper mass-produced parts, including a stamped sheet-metal receiver and a plywood buttstock and forward grip.
Russian weapons designer Mikhail Kalashnikov holding his best-known creation, the AK-47, 1997.
Vladimir Vyatkin/AP Images
Despite their obvious advantages, the AK-47 and the AKM were considered by the Soviet military to have problems with accuracy, mainly because of recoil forces generated by the powerful 7.62-mm round and other forces known as blowback that was generated by the weapons’ heavy internal mechanisms. Those problems were partly addressed during the 1970s when the AKM was replaced by the AK-74, which adapted the basic Kalashnikov design to a smaller 5.45-mm round with a higher muzzle velocity of 900 meters per second. A later version of the AK-74, the AK-74M, was the main infantry weapon of the Russian army into the 21st century.