Merle,
The real question is,,,is the bear a threat to you or trying to eat your ass? if so I'd use what ever I had in my hand then when that was empty for to the next closest thing, even if that was a rock!
Joking aside, a 357 with a good bullet will do the job, as a friend us to say with bears it's a matter of penetration! Some times a bear will have a lot of crap in his hide on top of a good amount of fat, covering heavy bone before you can even think of getting into the vitals, and they don't alway offer the best shot angel.
Not the perfect picture for a light weight varmint bullet out of a 223
I have seen a 45 auto 200 grain hard cast semi wad cutter HG68 in front of 7.gr of unique enter above the left eye and stop just under the skin behind below the right ear. This was at 7 yard. I also have seen a 135 gr FMJ out of a 38 Super punch clean through both sides ear to ear at 12 yards, Both Bears dropped hard. as others have said it has a lot to do with shot placement. if you go for a head shot you have to cut the apple to the core for good results
Personally I'd make the shot with either if is was out to get me, but if I called him in and wanted to take him for his hide,, I'd slip that 223 between the eye and the ear, for any shot over 15 yards. That is unless your pistol groups are smaller that your rifle groups out to 50 yards.
------------------
Keep your hooks sharp and you powder dry.
Wildoats
"The expactations of life depend upon diligence; the mechanic that would perfect his work must first sharpen his tools."
Confucius