really depends on the kind of elk terrain you'll be hunting.....in the timber?, open scree slopes, farms?

Our elk hunting has all been in the timber bordering agriculture or cut blocks, I'd say across 14 bulls, the average shot would be less than 70 yds, we did catch 2 out in the open block that would have been 200-250 yd shots.

For the way we hunt them,humping and bushwhacking for up to 10 hrs a day, what I would look for in a dedicated elk rifle, would be.....light as possible, compact as possible. Tikka t3x lite compact comes to mind, wildcat stocked rem mod 7 if building. Leupold 2-7x33 on top

For a cartridge i would want short action with some close range thump, coupled with 300-400 yd capability should the odd occasion arise when I needed to stretch it out a bit. Mild enough recoil to make for quick follow up shots if needed. i have a bit of a preference for 7mm over the 30 cals, so I would probably look at the classic 284 win pushing a 168 barnes lrx around 2650 fps. Plenty of oomph and any angle pass through up close, as well as holding over 2000 fps and over 1500 ft/lbs at 400yds.
If my style of hunting them, or my area made longer shots the norm....280ai will push that same 168 lrx up well over 2800 fps and give you plenty of range with reasonable recoil.

JMO
Chris