The 5.45 x 39mm cartridge is the main bullet made for short- and medium-range guns for the later Soviet and Russian militaries. It is used for guns like the AK-74, the RPK-74, the AN-94, the AK-100 series of rifles, and the AK-12. It is a Small Caliber High Velocity (SCHV) bullet, which means it is very small, but it has a high muzzle velocity and effective range.