I don't know much about bear spray, since I live in Alabama. But for any decent-sized animal, I think my .45 should work fairly well. The first round may not kill a bear-sized animal, but it should slow it down pretty well to allow me to squeeze off the other 20 rounds.

And I'm fairly sure that not much on this planet will keep coming after 21 rounds of .45acp 230-grain HydraShok. Maybe a moose or elephant, but my chances of running into one of those around here are pretty slim.