Well, if one is shooting elk at long range, maybe a Magnum is desirable if accuracy is enhanced, or the range is extreme.
On my Idaho hunt I carried my .338 Mag as shooting was likely to be up to 500 yards (my competence limit- not the rifle's) cross-canyon - and besides, it was the only rifle I had in Barrow - the rest were in storage elsewhere.
On my Colorado hunt the range was advised to probably be within 200 yards- likely about 50. The .260 with 140 grain Corelokt bang-flopped the cow at about 150..., but I did debate between it and the slightly heavier 17 inch barreled '06.
And it is 1 lb lighter.... and I hadn't killed with it before....
6 weeks prior my son had bang-flopped a caribou at 200 yards with the .260 ( virgin kill for both), and two weeks after the elk, that 40 yard wolf didn't complain- just died. I've killed caribou in excess of 300 yards with that 260 since, so I don't think Magnums are a needful thing to kill elk at any reasonable range. Especially if one can't shoot 'em.... But if one can, it can't hurt.
A critter just doesn't care what kills it.
