That kinda depends...American factory ammo is under loaded, and
is not much more powerful than a .30-30 in my opinion.
The #13 Speer Manual has 8 x 57 data that gets much closer
to the actual potential of this cartridge.
Barnes Bullets shows loads that push a 180 grain X Bullet
to 2,700 feet per second also. By golly, that should do it.
So, the way I see it, the 8 x 57 will handle Elk, but if we are
only talking about factory loads, then I'd prefer a .30-06.
( Unless there is somebody with a decent factory load that I
do not know about of course. )
That's my opinion anyway, others might not agree.