IMO the 357 might work great in the "right situation". But if you would move up the ladder to say the 44 mag or 45 colt you will get a few more "right situations"

Also if this is a once in a lifetime or an extremely hard to draw hunt. I would go all out on a "more proper" (if there is such a thing) elk cartridge. I would hate to think I would come home empty handed (and never get to hunt that hunt again)..........all because I had to pass a shot, or worse yet, not get the job done with a 357.