I have elk hunted with a group of friends in Wyoming every year for more than a decade now. All but one of us use 300 Win. Mag's. The odd man out shoots a .270 and he ends up getting a bull just as often as we do. For me personally, I feel more confident using my 300 shooting 165 grain barnes triple shock bullets. The 5x5 bull I killed this year was during a snowstorm and 450 yards away just at dark. He only went about 40 yards after being shot but we still had to use headlamps to find him (straight up the mountain). I'm not sure I would have taken the shot with a .270 but plenty of elk have been killed successfully with it.