The 280 looks like it might be fun, just a little different but not so different as to be a pain to find or make ammo.
Of all the posts thus far, I most agree with the recommendation of the .280, the bullet weights available will be sufficient, the velocity performance will be adequate for practical ranges, and the recoil will be quite tolerable to provide more pleasant practices= more frequent practices.
I believe the key is to pick a rifle that you can be comfortable enough with to fire round after round after round with boring consistency. Elk have been taken with .30-30's and .243's for decades, while this may not be a popular thought it is true. My grandma ran a .243 or a .25-06 till the day she died and with either one, her Montana critters had PLENTY to fear. I don't think that just any Joe Smith can do that, but Joe with 1000 rounds of accurate practice will be more successful than Joe with one box fired through his .300 win Mag. Bullet construction will make a MUCH more decisive factor than a debate over the lil .260 vs the big .338.
I've not yet taken an elk but all my family has lived/hunted WY/Co/Mt for decades and they've all made it clear, yes make the first shot count, and the second, and the third and the fourth, until that elk goes down. Don't bring a varmint bullet to an elk hunt, and KNOW your distance! I'm in decent shape but I'm not a mountain goat so I know I'd like a lightER rifle. I know I'm not great with pushing a 180 bullet at magnum speeds accurately with a lightER rifle. I choose to increase sectional density, use a bonded or monometal bullet, and get REAL comfortable shooting a 6.5 or 7mm out to as far as velocity determines practical as accurately as I need to to make an ethical kill. Ft-lbs is not what makes the kill and should be ignored. Velocity opens the bullet, sectional density helps determine penetration, and the local laws determine what's legal. Tons of people swear by the 6.5x55 Swede which has taken game in the elk class for decades, it's a VERY comfortable compromise if loaded, handled, and aimed properly. If you know someone who has anything chambered in the larger bore cartridges that will let you handle one for testing, give it a shot. If not, I'll sell you my .300 win Mag with a few factory loads and all the brass I've got for it for cheap
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