A bear can, from a standing start, cover 20 yards in about 1 second. They are incredibly quick animals. If they are already moving, with every intention of getting you, a bow, or holstered handgun is going to be too slow. Because an arrow kills by hemoraging, shooting one at a bear(unless you are lucky enough to spine or brain it) isn' t going to stop it. At least not right away. And it would only take a half second for one to kill you, if it wanted. Or possibly collapse on top of you while mauling you. Hopefully he' s not too big you can get him off of you!

A shotgun can be fired from the hip, with good results. You may only get one chance, so you have to make the first one count. Number 4 buck puts a lot of pellets in the right direction. Pepper spray is effective as well, but requires the bear to be in rather close(15 feet or less, I think ten feet is the recommended range to use it)). Always a good choice, especially if bear seasons are closed, and a good back-up to the shotgun. And lastly, a big non-folding knife carried on the belt is not the first choice but will work. Think about it, you fired once with your shotgun, perhaps missed or just grazed the bear. He keeps coming. By the time you' ve worked the action he' s on you and has knocked you to the ground and your gun from your hands, that leaves you with nothing. The knife works as a last resort and can be used with both hands. Go for the throat, or try to get the blade into the chest.