I'd like either a 300 Win or a 338 Win, with the 338 getting my nod for the heavier bullet weights. A 338 Win with the new Barnes 225 gr. TSX bullet is something I want to try.

Under the conditions which you have set:

8x68 S.
Period.

Carcano

I would agree that any of the 300 mags meet your description.
But you would not be hurt with a 7mm Mag. or 338 Mag. or a 30-06 would do for that mater.

I guess I would have to vote for any good 300 magnum shooting Nosler Partitions at 3050 to 3200 fps. They will shoot flat, hit hard, and not beat up the shooter too bad.

Don't get me wrong, I LOVE my .338 Win Mag. But the last elk I shot was with my 300 WBY Mag and the 180 Partition. I fired and it hit the dirt, right now! Some folks just do not like the recoil of a .338 or .340 Weatherby, etc.

I own a 7mm Wby Mag, but it would go with me on an elk hunt only if my 300 Wby Mag and 338 Win Mag were broken or stolen.

Elk are TOUGH animals, sometimes they take a lot of hammering to put them down.

R F

I have shot elk with a .280 thru the .338WM. They all got the job done. That said, I have shot 12 elk in 15 years of elk hunting. (all on self hunts I might add )None of them have been even 200 yards away much less 400. The rifle I liked best, because I could enjoy shooting it well enough to stay sharp with it while knowing it would get the job done even under perhaps adverse conditions, was a .300WM and a 200gr Grand Slam @2800+fps.
The year I hunted with a .280 all I had was a cow tag and I shot an antelope, a mulie, and a nice cow. All with a 145gr Grand Slam. No, I do not think the .280 is the ideal elk cartridge.