you can never tell what a deer will do when shot. I shot some in whatI thought not so great places and had then drop and others I drilled then in places I figured was a sure "plant you here hit" only to have then run off. If you really want to stop them right now, in almost for complete certainty has to be a shot that breaks or interrupts the spine of the animal. Solid spine hits in the back or neck seem to plant there 99% of the time. The problem is they are not the most easy shots to makes.

Head shots also work if you want to plant them, but he sure and hit the head/brain mass areaand not the jaw. There is nothing worse then seeing a deer running around starving to death with a broken or missing jaw. Also a word of warning, I have a friend that claims he shot a deer in the head with a roundball and it glanced off. It did knock the deer down, he reloaded, walked up to it, and it stood up, so he shot it again. When he inspected the head he claims there was a large chunk of hair missing where the ball hit and was deflected. I never saw the deer and sometimes this fellow I am referring to like to tell "a good story." It probably did happen but again, I never saw the deer.

The high shoulder shot is another that will put the deer down most of the time but not all of the time. Here again, I think that high shoulder hit breaks them down and disrupts the spine somewhat. I've dropped them by hitting them there.

I would just concern myself with putting the ball where it will destroy major organs; ie: heart and lungs. Roundballs when they get inside a deer can really take some strange paths. Good luck with your hunting.