Home Forums Hunting & Shooting General Big Game Bear protection: 9mm, 40 S&W, 45 ACP?

Well, yes and no. I've had analytical dealings with GSW's on human skulls more often than bear skulls, so you can take my advice with a grain of salt if you like. But the problem with punching through the skull is most of the time not so much due to the caliber or shape or construction of the bullet, but the angle at which the bullet strikes the skull.

I've seen (and treated) guys walking and talking who've been shot in the head at close range with 9mm, .40 S&W, and .45 ACP and because the bullets hit the skull at too much of an angle, the bullets failed to penetrate the bone and simply tunneled around under the scalp. One guy survived 4 hits from police 180 gr .40 caliber GDHP's, but was conscious and talking to me in the ER. If you think about it, this makes sense: our skulls (and those of our relatives in the animal kingdom) evolved as rounded/pointed shapes because these shapes reflect blows/missiles more effectively than square shapes.

A .22LR soft lead bullet will punch through the skull at close range if it strikes the skull at close to 90 degrees. Now, I'm sure you increase your wiggle room in terms of angle if you ramp up the velocity or use a sharp-shouldered WFN bullet, but even then you can't underestimate the design features of mammalian skulls.

As Phil pointed out--and I will not comment on the number of bears, or beers, he has under his belt--a 9mm 147 gr bullet has more than enough punch to drill a hole thru the skull and into the medulla of any bruin walking this earth. But you'd best place that shot at an angle as close to perpendicular as you can manage, just to be sure.