Will a 7.62x39 Penetrate Kevlar NIJ III?

Yes — defeats a 5 mm kevlar nij iii barrier
Penetration depth
9 mm (0.4″)
Impact velocity
715 m/s (2346 fps)
Muzzle energy
2045 J (1508 ft-lb)
Bullet behaviour
Intact

Fired at the muzzle, a representative 7.62x39 load (8 g, FMJ, 715 m/s) reaches roughly 9 mm (0.4 inches) into kevlar nij iii. That is enough to defeat a typical barrier of this material — treat anything behind it as exposed.

About Kevlar NIJ III

A soft body-armor panel is roughly 5 mm of layered Kevlar.

7.62x39 against other materials

MaterialDepth (mm)Depth (in)
Red Brick187 mm7.4″
Concrete137 mm5.4″
Tempered Glass29 mm1.1″
Steel A3613 mm0.5″
Steel AR5004 mm0.2″
See exactly what 7.62x39 does to Kevlar NIJ III — open in the calculator →

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