AK-74 be used by the majority of countries of the former Soviet Union. Additionally, licensed copies were produced in Bulgaria (AK-74, AKS-74 and AKS-74U), and the former East Germany (MPi-AK-74N, MPi-AKS-74N, MPi-AKS-74NK). Besides former Soviet republics and eastern European countries, Mongolia, North Korean Special Forces, and Vietnamese People's Naval infantry use AK-74s. The AK-74 was designed by А. D. Kryakushin's group under the design supervision of Mikhail Kalashnikov and is an adaptation of the 7.62×39mm AKM assault rifle and features several important design improvements. These improvements were primarily the result of converting the rifle to the intermediate-caliber high velocity 5.45×39mm cartridge.
AK-47 of the USSR. The Soviets were impressed with the weapon and immediately set about developing an intermediate caliber fully automatic rifle of their own, to replace the PPSh-41 submachine guns and outdated Mosin–Nagant bolt-action rifles that armed most of the Soviet Army. The Soviets soon developed the 7.62×39mm M43 cartridge, the semi-automatic SKS carbine and the RPD light machine gun. Shortly after World War II, the Soviets developed the AK-47 assault rifle, which would quickly replace the SKS in Soviet service. Introduced in 1959, the AKM is a lighter stamped steel version and the most ubiquitous variant of the entire