Guns for elk this is a ? that is asked alot.We all no the debate Caliber vs Placement.
I'm going to break this down in to three groups of calibers.
1.There are guns that will kill elk.
243,6mm,25-06,257 roberts,250 savage,30-30,32 win special and so on.
These guns are calibers that are on the light side,very light at that.
Thes are the calibers you see pepole buying for their kids,wife,girl-freind to hunt deer and elk with.when in all sense these should only be used by some one who has nerves of steel and can pick their shot.
2.These guns are what I call cross-over elk rifles(I mean you are deer hunting in the mountains and you come a cross a bull or cow,you go "OH $hit theres a elk,BLAM"
These I group as .308 win,270 win,280 rem,7mm-08,260 rem,6.5x55 S,30-06, 257 Weaterby,270 wsm.
Now these guns work and do a good job,been doing it for years but they are not true elk guns,just cross overs.

Now group #3 are elk guns and are what you see alot of pepole packing.
.300 win,Rem Ultra,rem Ultra short,.300 wsm,7mm rem,Ultra,Ultra Short,WSM, 35 whelen, .350 Rem Mag., .338 win,Rem Ultra., .375 H&H.Rem Ultra and so on I go as big as you want.I would shoot an elk with a 416 Rem Mag and not feel guilty about it.

Now I call my .338 Win Mag a deer-elk cross over or my .300's.
My .375 H&H is a true elk gun if I want to pack it.
As with any gun Shot placement is the key,you don't have to hug the shoulder on a elk, the vitals are almost 2 as big as a deer.