My great grandfather used .22 shorts to put down 400+ pound domestic hogs when it came time to slaughter. No problems at all if the pig was calm and the muzzle could be brought up just behind the ear for a perfect shot. Doesn't mean I'm gonna go pig hunting with one. Years ago I came upon a coyote with a .22 rifle in my hand. I put the first bullet in his head. He fell down and to my surprise, got up again. That continued more times than I care to admit, until he made it into a brush pile a few feet away and I couldn't see him anymore. I know a fellow who was shot in the guts with a small caliber handgun. Lost a few feet of intestine as a result. I'm pretty sure the one that shot him regretted making him angry with a peashooter too.
BTPOST, The ballistics are right here from a 3.5 inch barrel. This is the same pistol I and my wife have.
As for head shots?? We are real good shots but would not attempt one unless the target was standing still. Center mass only. and moving away from the threat . We have done 50 times more shooting with the .22 pistols as we did with the 9mm. Ammo cost was the reason. We were able to get that extension of your hand instinctive shooting thing down with these pistols because we shoot them a lot. But again I AM NOT NOR WILL I EVER ADVOCATE USING A .22 FOR DEFENSE. I am not a handgun guy. If I had to use one for defense it would be a .44 magnum.
Until you have been in a Gunfight you are just guessing which round is best....science has never been in a gunfight.....
I read of a gun fight between a cop and big biker and they exchanged fire in each other embrace the cop shot the biker several times in the belly and lived, and the biker shot the cop once in the ribs and the cop died. The cop was shooting .40 and the biker was shooting a .22 . I've read also of a Alaskan guide that can shoot a bear in the eye with a .22 and drop him right there. Bullet placement is critical. practice in a panic is critical,(warrior mentality) If you don't train to act, your wasting time.
@arleigh .. People write all kinds of BS, in this world, but I tell you that No Alaskan Guide, worth his Salt, or Brains, is guiding, with a .22LR as his Security Weapon.... Many use Marlin 45/70 Guide Guns, as a Minimum, and plenty carry much Bigger Weapons, out in the bush.... Unless you are a World Class HandGunner, there isn't a Hand Cannon made, that is sufficient for Coastal Brown Bear Protection, out in the bush.... and anyone who tells you different, is either a Lier, or an Idiot, who you should avoid at all costs.... and our Bears aren't the only thing out here, that will Kill you just for being there.... A Moose is just as likely to STOMP You, as walk on by....