I have launched bear bangers and they have exploded at the bears face.......not the desired effect, sure he ran off a ways but the trick is to ensure they don't come back. We don't feed the bears, we keep bird feeders only during hibernation times. Our garbage is bagged,canned and left in the garage until garbage day. The compost is heavily limed, we do this to minimize contact with black bears. There is lots of wild berries and food around now, they do not need to come around the house. Part of the problem is that these troublesome bears may never have encountered man before, thats why I would like to impress upon them that we are not their pals or food for thought. Its all a small price to pay for living in the wilderness.