bentbarrel, the only black bear I have taken with a rifle was with a 270 win, the rest have been with an arrow. The shot was 75 yards and he was over 300lbs, dropped with one shot. As mentioned they are not very tough to kill, especially with a rifle. My hunting partner has killed several bears being raised in bear country and a sheep/cattle farming operation, with his trusty 3030.

My suggestion is take the rifle that gives you the most confidence and shoots the best. I would run solid constructed bullets such as: failsafe, aframes, trophy bonded, nolser parts, etc just due to the large/heavy shoulder blades they have.

Best of luck on getting a nice blackie!