It's an odd question, and possibly slightly disturbing, but can a .22LR fired out of a typical little pocket .22 pistol penetrate a human skull? If I buy a .22 to carry, is it completely useless trying to aim for someone's head because the bullet will just glance off their skull? I'd probably be using nice, hot ammo, if that matters. I'm definitly not going to rely 100% on a .22 for self defense for my entire life, or expect it to work with one shot, but when I turn 21 (California - ugh), I'd probably have an easier time convincing a local sheriff to let me carry a $100-$250 .22 than a nice $600 .45ACP. On top of it being easier to conceal, cheaper to buy, and far cheaper to practice shooting with, it'd be convenient, even though not the most effective. Hey, I'd have something, right? Better than a knife, that's for sure.