Excellent advice (from Ramrod) since the more you practice, generally, the better you get.
HOWEVER
you must also take into account that a .308 in an Encore will have, I suspect, a pretty hefty kick due to the relatively light weight of the firearm. But if you intend to mix elk along with your venison, then the .308 is certainly the better choice.
As far is there not being much difference between an elk and a deer (J.Rs thinking)
I think someone has been giving you bad advice. There is a HUGE difference between the two animals
not only in size, but in tenacity! The elk is MUCH larger and TOUGHER
while your .308 Win. Cartridge is a fine deer cartridge, its BARELY an elk cartridge in many seasoned hunters opinions.
In fact, for elk hunting, Id strongly urge you to use Federals High Energy or Hornadys Light Magnum .308 Win. cartridge for elk and keep your shots UNDER 200 yards
or better yet, under 150 yards using a .308 Winchester.
To give you an idea of my thinking on the two animals, I hunt deer with a Model 99 Savage in .300 Savage caliber... the "father" of the .308 Win. cartridge. However, I used my pre-'64 Model 70 Winchester in .338 Win. Magnum to hunt elk in Colorado and moose in Canada.
I've always believed in "matching" the caliber to the game hunted... and these calibers on these game animals are a perfect match in my opinion.
But... most important of all (on either elk or deer, but especially on elk), place your shot CAREFULLY
put your bullet into the elks boiler room (2/3s of the way down from the line-of-the-back, just behind the shoulder)... and with a 7mm/08, a .308 Win. or a .338 Win. Magnum, you'll be eating elk steaks & roasts after the hunt while the icy Winter winds blow just outside your kitchen window.
If you dont place your bullet well, you may learn a "hard lesson" about an elks tenacity when you have to trail a wounded elk up & down over many ridges for several miles. Packing out the meat over THAT distance can and does become a major problem.
While Im not completely familiar with the Encore, I understand that one of its best features & greatest advantages is that it can use inter-changeable barrels, so why not opt for a 7mm/08 barrel for deer (now) and a .308 (or larger caliber
like a .358 Win.) barrel for elk if you decide to hunt elk at some point in the future?
Regardless of what you decide
may the gods-of-the-hunt smile on you and bring you only good luck. :-)
Strength & Honor
Ron T.