I once she a muley buck that dropped like a rock on impact, a couple seconds later he jumped up and took off. We found bone like that close by. We found him not more than about fifty yards from where I shot him. What happened was the bullet hit his brisket and shattered bone but I was lucky and a piece of bone shot up and hit a major artery next to the spine. Pure luck. If that had not happened, he would have gone on forever.