Think I read of an old maneater monster Alaskan Grizz who killed many folk but finally a man and a woman sightseer, partially ate them and then attacked a hunter with a 7 mag who shot the animal ?(5)multiple times with apparent minimal effect before the creature died.The hunter reloaded for the killing shots.The monster bear is displayed at a fed site somewhere.

I think a proper stopping gun would be 458 class(not 45-70!) and NOT a shotgun, although smaller rifle calibers will obviously kill a non charging animal.