I too would not believe how far things can run while being dead, just not knowing it yet. Wouldn't believe it except that I've seen it. It's why I like exit wounds. Unless you can guarantee that you're NEVER going to be off by more than half an inch at any distance from any shooting position, you can't make hitting the brain or spine your entire strategy. It's a bad strategy. And sometimes no matter what caliber and shot placement (unless it's the CNS) the critter isn't going down immediately and there's nothing that changes that fact. Exit wounds (especially in snow) are wonderful things.
The animals mental state at time of impact matters too, not just the adrenaline after it's hit. The craziest thing I've seen was a whitetail buck (I don't know why elk get a reputation of being sooooo much tougher than deer…just that they're bigger and can soak up more of a hit but holy smokes I've seen boring old deer exhibit mental determination that nothing would outdo).
Broadside, slightly quartering toward, 200 ish yards with a 270. Hornady 130 interlock at 3200 fps muzzle. Perfect performance, exited after absolutely blowing up the chest, smashed the shoulder going in, completely severed big arteries right at the heart, fragment actually in the heart, totally destroyed/shredded offside lung, AMD THERE WAS A 3 inch or so CHUNK OF RIB-BONE just laying in the snow at the end of a vivid bright (lung) red spray in the snow about 8 feet long. Wouldn't have mattered if it was a .300 rum or a flipping 460 wby i don't think. So much damage. And he covered half a mile in thick brush up and down ravines. Was a real work out getting him.
When I pulled the trigger he was looking right at me with his tail up. Right before that he was chasing two does who seemed to not be trying that hard to evade his attention if you know what I mean
. So he thought he was about to get lucky, pumped right full of testosterone and then pre-shot adrenaline cuz he noticed me and was already on high alert at the shot. I am convinced that had he been alone and not noticed me there's no way he would have gone even a third that far.