I just got a deer last sunday during our rifle season. 80gr 3F shutzen, .018 pillow ticking with a .490 ball. At 30 yds broke her spine, ripped though her heart and took out 1 lung, it did not exit, and she went down like an anvil had fallen on her. Day before, clean miss, but at 100yds buried itself in a tree about 4 inchs(i dug it out) after it gouged another tree. She was in a shadow and it looked like the tree was behind her NOT in front of her. AT least it was a clean miss, and not a ding. I think anywhere from 60-90 grains will bring down most any whitetail, just depends more on what your rifle prefers.