I was always under the impression, you want the bullet to not exit the animal, ad more momentum will be used inside the body cavity making a cleaner kill. I never thought it was very accurate because, I've seen my dad hit deer with his .300 Weatherby Mag, and drop 'em where they stand, and I've seen people hit deer with smaller calibers where there's no exit wound and we've had to track deer for hours. I hunted with a 12GA for years, and I've only ever dropped 1 deer where she stood and I was aiming high and I had one pellet hit her right above the eye at 85 yards. And the bullets never came out the other side.