Wounding potential of the Russian AK-74 assault rifle.

The Russian contribution to the new generation of smaller caliber assault rifles is the AK-74, whose 5.61-mm (diameter), 3.4-gm (weight), 2.5-cm (length) aerodynamically shaped bullet has a muzzle velocity of 900 m/s. Our tests show that in living swine soft tissues and gelatin tissue simulant the AK-74's copper-plated steel jacket resists fragmentation or deformation. Since the bullet does not fragment, the tissue disruption surrounding the bullet pathway is limited to the stretching effect of temporary cavitation. We present evidence indicating that the energy used during temporary cavity formation causes limited permanent tissue disruption in the more elastic soft tissues (muscle, bowel wall, lung); the same insult in the relatively nonelastic liver, however, causes multiple fractures and massive permanent disruption. We conclude that the AK-74, despite its rather high velocity and marked tendency to yaw soon after penetration, causes relatively nondramatic wounds due to its nonfragmenting behavior.