It's been a while since I've packed-out an elk or moose…..but was never disappointed with my "freighter" frame! It was more capable than I…..even though when I was much younger, I'm reasonably certain that I had 150+ pounds on it a time or two!
Carrying out an entire deer or sheep (boned-out) with the head was a "piece of cake"!
Of course, shooting babies helped a great deal! memtb
Kelty Tioga or Serac 70's era stuff but, nowdays thinkN they call it Trekker 65. Good welded external aluminum frame, take all the bags off to pack Elk venison. Leave the bones behind, use cloth game bags.
My last elk I packed out with a Kuiu pro pack system. Worked great. The trick with any of these packs is getting a proper fit on your body. A poor fit or poor weight placement can make any pack suck. The closer to your body the better.
I use Mystery Ranch for pretty much all hunting. Elk, deer, moose, sheep, whatever I can get a tag for.
My three I use the most are the Marshall for 5+ days, the Metcalf for 3 days, the Pintler for colder 1 day outings, and the pop up 38 for warmer 1 day outings.
I think you will really like the XO. I got a K4 this year and although I didn't pack out an elk this year I have used it for training and while hunting. I have had loads up to 100 lbs and been very happy with it. Due to the lack of a butt I have had slippage issues with other packs in the past. The K4 has worked very well. I am very happy with it and the customer service is unbeatable.