Firearm a battle rifle such as the Karabiner 98k, but the chief differences defining an assault rifle are select-fire capability and the use of a rifle round of lesser power, known as an intermediate cartridge. Soviet engineer Mikhail Kalashnikov quickly adapted the German concept, using a less-powerful 7.62×39mm cartridge derived from the standard 7.62×54mmR Russian battle rifle round, to produce the AK-47, which has become the world's most widely used assault rifle. Soon after World War II, the Automatic Kalashnikov AK-47 assault rifle began to be fielded by the Soviet Union and its allies in the Eastern Bloc, as well as
Comparison of the AK-47 and M16 receiver/barrel. Or, an M16A4 Rifle can be converted to an M4 Carbine in a few minutes by replacing the upper receiver/barrel and using simple hand-tools to replace the fixed buttstock with a telescoping buttstock. As such, the M16 can be easily converted into different calibers and different types of weapons. The AK-47 has no such capability. Today, bayonets are rarely used in combat. However, both the AK-47 and M16 retain bayonet lugs and bayonets are still issued. Also, bayonets are still used for controlling prisoners and as a weapon of "last resort". In addition, some authorities have concluded that bayonets