I was reading an old artical in Outdoor Life about a Grizzly hunt that went wrong. The Bear was originally hit three times with a 300 Win Mag. The bear then charged and took four hits from a 44 Mag pistol. this stopped the charge but the bear was then hit three times with a 375 H&H then ran off and was found several hundred yards away dead. Once they charge it about takes a brain or spine shot to put them down quick. This could be delievered by any medium to large rifle, say a 7x57 on up. However hitting the spine or brain on a moving target is not an easy task. In the above story the guide said that almost all of the hits should have stopped the bear as far as shot placement goes. As we all know it doesn't always happen. 95% of the time one good hit from a 30-06 class and up rifle will put a grizzly down and even if it does not in most cases the bear will try to run away. However when a person decides to go into their domain after them you take the chance that you may finish second.Accept that or stay away from them. Same goes for any dangerous game.