The most spectacular Kills I've ever seen have been made with 140 gr 7mm and 150 gr .30 bullets. I've seen plenty of deer killed with these and have never seen 1 get away-indeed most dropped in their tracks. Rarely do they pass all the way thru but that's fine as they expend all their energy in the deer. A 7mm or .30 bullet of this type has more than enough penetration to get inside vitals before expanding violently.