Hmm! I hunted with the 270 Winchester for many years and harvested many mule deer, whitetail deer, antelope and even elk and bear. I loaded 130 grain cup and core spire point Bullets to 3100fps back then. I found that in hunting one does not always get the perfect standing broadside shot on that once in a lifetime trophy. My best mule deer buck in 1984 only offered a quick moving shot. After a long tracking ordeal in the mountains I was able to put 3 more Bullets in him and he finally dropped. Some animals are tougher than others and take more. The cup and core bullets shed weight, petals and jacket which limits deep penetration and lethal damage. I switched to a 300 magnum with 180 grain Bullets for more energy and penetration. I then switched to the all copper Bullets when they first came out to get better weight retention. I even went down to 150 grain all copper Bullets at 3200fps with great results. I have harvested deer, elk, bear, kudu, gemsbok, wildebeest and Dall Sheep with the 300 magnum and all copper bullets. I have had much better penetration and instant drop on the spot harvests with the larger diameter heavier 30 cal all copper Bullets. In a 30 cal magnum you can always shoot lighter all copper bullets in medium game and go up in bullet weight for larger game.