The norm recommendedfor moose, elk and bear is 1800 footpounds at impact. 400 yard shots aren't something to be taken lightly. An animal feels pain the same as we do, and I've seen too many people take potshots at game when they couldn't hit the inside of a barn. Practice makes perfect. A 338 will definately fill the bill for this purpose, but if you don't like recoil, I'd look at a 300 mag or something in the same class.