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″
Run your own numbers in the calculator →

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