By Guns Network Member - Devil Dog

I just completed a series of tests to determine the armor piercing qualities of the 7.62x39 cartridge. The targets were mild steel plates 12" x 12" x 1/8", 3/16" and 1/4 ". All firing was done at 25 paces with the target plates held vertical in a wooden stand. Firing was done offhand with a pre-ban AKM type rifle. Cartridges used were Chinese and Bulgarian steel core ball, Chinese lead core ball with steel jacket, Russian hollow point with steel jacket, and Soviet Armor Piercing Incendiary (steel jacket, hardened steel core and White Phosphorus point filler). All cartridge types easily penetrated all individual thickness plates, including the 1/4" thick plate. The plates were then stacked one in front of the other, with the 3/16" plate in front of the 1/4" plate followed by the 1/8" thick plate. There was an approximate 1/8" gap between the plates. This is where things got interesting.  All projectiles penetrated the first plate, but the Russian hollow point disintegrated upon contact with the second plate, leaving a moderate dent. The lead core ball projectile left a larger dent in the second plate and "mushroomed" into a near perfect half-sphere shape with the core and jacket typically remaining together. The steel core ball left an even larger dent in the 1/4" second plate, somewhat "mushrooming" with the core and jacket staying together and the steel core swaging itself into the shape of the dent on the plate. About half of the test shots were actually imbedded in the second plate and  were difficult to remove. The Soviet API projectile shed it's jacket during penetration of the first plate with a rather large "puff" of white smoke and the pointed, hardened steel core penetrated the second and third plates. The core actually broke in half at the mid-point, with the rear half stuck in the 1/4" plate and the front portion sticking out of the last plate (1/8"). Overall results were disappointing as the steel core ball cartridges showed little increase in penetration over the lead core  projectiles and the API projectile proved to be a disappointment in that expected penetration was not achieved. A second round of tests will be conducted using thicker plates, as I believe that the gap between plates spoiled the momentum and ballistic shape of the projectile from plate to plate. The poor performance of the Soviet API could explain why the Soviets did not produce this type after the late 1950's.