I'm looking to turn the great bear rather than kill it.
And then what, wishful thinking??? You'd be better off with bear spray.
Put the bullet in the right place and it will work, as well as any rifle. The question with properly loaded big bore sixguns is not whether or not they work, we know they work, the issue is whether or not the shooter can put the bullet in the right place. Spray the bear's face with birdshot and now he is injured and even angrier than before. If 400gr bullets from a .416 tear through his lungs and shatters the bear's paw and he doesn't even react, what do you think a faceful of birdshot is going to do?