Many years ago, I saw a guy kill a black bear with a 22 Colt Huntsman pistol. He was in a very bad situation and had no choice but to shoot and had no other weapon. He shot the bear three times the last shot being point blank in the head as the bear was coming at him from above on a steep hillside. The bear still ran over him as it tumbled down the mountain and then ran a ways before dying. I guess you use what you have available. I think that guy is really lucky to still be here today, and I know he carries a .44 magnum rifle when he goes out in the woods most times now.