've shot a few black bears............but that was with the archery gear. It was effective and final but the bears are tough.
I carried a 629 in a shoulder holster back then and one day had the chance to dig it out when a average size black bear was rounding the bend on the trail and we would meet at about 15'. I had a sweater pullover on over the shoulder holster and it was like a monkey loosing his balance on a tight rope trying to dig it out. The end result was that we never met as he decided to fade away, perhaps due to all the gyrations I had going on.
Today if I was fly fishing in bear country I would opt for a G22 with my 180 reloads that I shoot a lot with and am accurate. The gun is familiar and I can hit stuff with it. It is loaded and shot most of the time with 180g cast at 1167 fps which is on the warm side and comparable to many over the counter 10mm 180g loads, not the premium stuff but the everyday stuff.
No sweater over it now would be the rule and practice with it a lot. Seems like a good tool for me.
