Re: 338 lapua vs 338rum vs 300win mag vs 308
Do you want to kill elk at 1,500 yards, deer at 1,000, elk at 800, or deer at 500 yards? Until we know what range you want to shoot & what power is needed on the target, it's impossible to suggest an "ideal" round.
If you are new to longer range shooting but want enough power to kill at extended ranges I would suggest you narrow your focus to the following: .300 wsm, .300 win, 7MM wsm, .270 wsm, & 7MM Rem. These are not horrendously expensive to shoot, have tolerable recoil, are good hunting rounds for many species, and are chambered in rifles you don't need a second mortgage to buy.