Years ago when I was still young and poor I couldn't afford anything special for packing game out so I used my Dad's old wooden framed Trapper Nelson.
Over the years I did the gauntlet of cheap aluminum framed packs but I now use a Wilderness Wanderer external framed pack with a main sack and 2 add on bags these are made Kamloops.
Last fall we strapped an entire 5 point mule deer buck that weighed 158lbs field dressed onto the pack and we took turns carrying it out, we were just north of Williams Lake on the West side of the river.
25 years ago when I first started going into the Flathead River Valley in SE BC most of the logging roads were deactivated or closed to motor vehicle use so I bought a light weight plastic deep tubed wheel barrow probably carried 25 Mule deer out on it.
My buddies and I then built a light weight carrier unit much like the one Sheephunter posted earlier we used Mountain bike tires and later modified it with brakes so we had brakes for going down steeper hills.