RE: back from my backpack interior hunt
Sounds awesome! I enjoyed your story.
I personally use a Gregory backpack, an expensiveinternal frame granola-type pack. I've now hauled 5 elk out with it, distances from 3 to 9 1/2 miles. I've boned most of them out so there's really nothing gained with an external frame.
Tip: if you pack out boned meat it rides like a load of cannonballs. To prevent the meat from sinking to the bottom of the pack and forcing you to walk with your titties hitting your knees, use those styrofoam packing peanuts in the bottom of your pack. You can fill the lower 1/4 to 1/2 of the pack compartment with a garbage bag full of the peanuts - prob. weight under 1 lb. - and that will keep your center of gravity up where it belongs.