The 7.62x39mm cartridge is a rimless bottlenecked intermediate cartridge widely recognized for its use in the AK-47 and related firearms. It measures approximately 7.62 millimeters in diameter, which is equivalent to roughly 0.3 inches. This measurement refers to the bullet diameter, not the overall cartridge length. A common misconception is that 7.62 refers to the cartridge case length, which in this instance is 39mm. This particular cartridge delivers significant stopping power and has proven effective at medium ranges.
Developed in the Soviet Union during World War II, this round became a staple of militaries across the globe during the Cold War and continues to be widely used today. Its relatively compact size allows for greater ammunition capacity in magazines compared to larger, full-powered rifle cartridges. The widespread adoption of this ammunition type led to economies of scale, making it a relatively inexpensive and readily available option. This affordability and availability, coupled with the robust and reliable nature of the firearms chambered for it, contributed significantly to its proliferation.