Will a .308 Winchester Penetrate Tempered Glass?

Yes — defeats a 6 mm tempered glass barrier
Penetration depth
36 mm (1.4″)
Impact velocity
840 m/s (2756 fps)
Muzzle energy
3352 J (2472 ft-lb)
Bullet behaviour
Intact

Fired at the muzzle, a representative .308 Winchester load (9.5 g, FMJ, 840 m/s) reaches roughly 36 mm (1.4 inches) into tempered glass. That is enough to defeat a typical barrier of this material — treat anything behind it as exposed.

About Tempered Glass

Tempered and automotive glass runs about 6 mm thick.

.308 Winchester against other materials

MaterialDepth (mm)Depth (in)
Red Brick239 mm9.4″
Concrete199 mm7.8″
Steel A3617 mm0.7″
Steel AR5008 mm0.3″
Aluminum 606132 mm1.2″
Run your own numbers in the calculator →

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