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″
See exactly what .308 Winchester does to Tempered Glass — open in the calculator →

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