If it has to be a handgun go with the .44 and heavy 300-grain Federal Castcore or one of the other heavy hardcast lead bullets like the Garrett loads.
I have never been attacked by a bear, but I have met one pretty close. There was a time I had reasonable faith in a .44 Ruger Redhawk and huge bullets "for bear", but having read some specific case histories I would no longer feel quite so confident. I would recommend that you study up on bear anatomy, and how this translates into 3-D when they are running fast from the front. Even heavy pistol pistol bullets will likely deflect on the skull - even if you can hit it. Most bear attacks are generally recounted as fast and furious, from very close. In other words - about a second and a half, maybe two seconds, notice.
Everything I have read about black bear says they will turn even if they are wounded. They can climb trees very fast, and very well.
Grizzlies can, even if the heart is destroyed, still tear you up for quite a time - though that doesn't mean to say a minor hit has "never" turned a grizzly too, just that I would count on the opposite. I have read conflicting things about grizzlies and climbing trees; some say they "can't" some say "can". Whatever the case, on their hind legs they can reach very high off the ground. Something to keep in mind.
Of course never attempt to outrun either. I do know a lady who, after a surprize encounter with a bear, managed to make it to her truck cab with a pretty slim margin. She said it was "pretty close", despite the fact that the bear was quite a distance away at the "start". Bears can sprint - very fast.
But forget the 10mm. Better, as has been suggested already, is a rifle. My own choice would probably be a 12-gauge shotgun loaded with Brenneke slugs. Probably a double; automatic ejectors, and double triggers, 18-20" barrels, with a buttstock-band type shell carrier with extras. That - or a pump.
I have never been attacked by a bear, but I have met one pretty close. There was a time I had reasonable faith in a .44 Ruger Redhawk and huge bullets "for bear", but having read some specific case histories I would no longer feel quite so confident. I would recommend that you study up on bear anatomy, and how this translates into 3-D when they are running fast from the front. Even heavy pistol pistol bullets will likely deflect on the skull - even if you can hit it. Most bear attacks are generally recounted as fast and furious, from very close. In other words - about a second and a half, maybe two seconds, notice.
Everything I have read about black bear says they will turn even if they are wounded. They can climb trees very fast, and very well.
Grizzlies can, even if the heart is destroyed, still tear you up for quite a time - though that doesn't mean to say a minor hit has "never" turned a grizzly too, just that I would count on the opposite. I have read conflicting things about grizzlies and climbing trees; some say they "can't" some say "can". Whatever the case, on their hind legs they can reach very high off the ground. Something to keep in mind.
Of course never attempt to outrun either. I do know a lady who, after a surprize encounter with a bear, managed to make it to her truck cab with a pretty slim margin. She said it was "pretty close", despite the fact that the bear was quite a distance away at the "start". Bears can sprint - very fast.
But forget the 10mm. Better, as has been suggested already, is a rifle. My own choice would probably be a 12-gauge shotgun loaded with Brenneke slugs. Probably a double; automatic ejectors, and double triggers, 18-20" barrels, with a buttstock-band type shell carrier with extras. That - or a pump.
