I have a 28 in. 5R heavy varmint contour barrel on my 300 RUM. I'm thinking if I wanted to fry my barrel I could get 4000 fps with a 110 to 125 gr. Bullet but something about a 215 gr. Berger Hybrid at 3140 fps. Works for me on elk , deer and lope. I'm not against hyper fps at all. You have me thinking now about a125 gr. at 4000 fps for lope beyond 500 yds. Interesting.