HBP
I second Dogfishes comments. I am a archery hunter in Oregon but use a rife in other states. The 270 is a sweetheart to shoot and is a deadly elk round in the hands of an experienced hunter.
Long ago a writer by the name of Jack O'Conner was a champion of the 270. He took elk in two and in some years three different states, for over three decades, most where with the .270. For years(50's,60's & 70's) the great debate was over which was the best allround rife, the 06 or the 270. Once in a while the 7x57 would sneak into the arguement. For what it's worth one of my duck club members shoots an 06 in Africa each year on Lion. He likes it because its what he can shoot well(an understatement)and there is ammo any where he goes. Does that tell you how good that round is regarded in Africa? I own both and it is my opinion the elk never had the slightest idea which one killed him with just that one shot. Dogfish tells it like it is, shot placement! Shooting 500 yards at a moving elk is not my idea of sport. I like to HUNT. There is nothing wrong with using bigger stuff on up to .375. Its a matter of what you can handle well. If your friend is able to place the bullet where it belongs , it isn't going to make any difference. For what its worth I use the 130 gr. without a problem. I will say up front I don't hunt in areas where there are as many hunters as elk. I am not a good off-hand shot and use a tree, bush or anything else for a rest, and I use a scope.
I'm sorry for being long winded but your friend should have confidence in what he is hunting with.