No its not. In fact, it might endanger you and innocent bystanders. The bullet bouncing off the bear could ricochet in an unknown direction. It could hit and possibly kill someone. To kill black bears you need a cartridge with at least three adjectives in its name. For example, super, duper, hyper magnum.
Stick to game no larger then chipmunks with a .30-30. Then make sure the range is short and you go for head shots to ensure humane kills.