TTAG commentator jlp uploaded this underneath our post Carry Gun: A Bear Necessity?
In 1945 the U.S. Military tested the .45 acp with military 225 grain bullets V/S the 9×19 with the 125 grain bullet. The anemic .45 acp bounced off a helmet at a scant 35 yards while the 9mm penetrated the helmet at an astonishing 125 yards and may have been able to do it even farther but the accuracy of the gun and the skill of the shooter was beyond its capability to make any hits at any farther ranges . . .
P.O. Ackley when shooting into a U.S. Army Half Track with 1/2 inch hardened armor plate blasted right through it with nothing more than a .220 Swift using 48 grain soft point bullets while the 30-06 with armor piercing rounds with a steel penetrator core bounced off the half track. Ackley when shooting feral mules found the .220 Swift was the ultimate killer caliber fare surpassing the military calibers he also used.
The Old .228 Savage rifle with an 70 grain bullet was used to kill Grizzly Barrels early in the 1900’s. Now in modern times people use the .223 …Read the Rest
Source:: Truth About Guns