Here' s a factual situation from a fortnight ago.
My hunting buddy Kevin stalked a Wapiti Bull that was bugling it' s lungs out. He only gave one Bull call, and this animal became totally enraged, it came crashing toward him, really worked up. He steadies himself, takes aim and decides on a head shot, as the animal was only 40 yards out. The bullet entered just below the eye and exited out the back of the skull. The animal dropped in it' s tracks, but then got up and kept on coming at him. His second shot was in the neck. The bullet entered about 8 inchs below the head and took out the windpipe, it did not however hit the spine/neck bones. The animal collapsed again, but again it found it' s feet and just kept on coming. Kev was getting real nervous at this stage as the rifle only takes three rounds. The third shot from about 10 yards was into the chest. It took the top off the heart and smashed ribs and one leg bone. This time the animal went down for good. The rifle was a Sauer .270. The Ammo Federal Premium Factory Load in 130 grain.
We are both amazed how tough it is to put an animal down when he is full of adrenalin. The animal was a large bodied and very old Bull.