When I killed my first elk I had a daypack on my back and couldn't take a load out with me on the first trip. I won't do that again, and since that time have been using Eberlestock packs, first with a J104 and now a Blue Widow. They are also large enough and do a great job with heavy loads, so I sold my external frame pack. Compresses down small enough that I can hunt with it, yet expands to carry as much as I'm willing. They are also large enough and do a great job with heavy loads, so I sold my external frame pack.
Another great Eberlestock pack for the first trip out with meat is the X2. I prefer a larger pack for serious meat packing, but it will do a fine job on that first trip out. They are probably the most popular pack with big game hunters that I sell.