Try doing this for a tent. Of course if you use the surplus poncho, poncho-liner for bed-roll, fiber-glass tent poles and a plastic trash-bag or drop-cloth for the ground-cloth you will be much bulkier, colder, and heavier but much cheaper. But, If you spend the $40 for the poncho, the $110 for the sleeping bag, the ~$140 for the carbon fiber custom tent poles, and the few bucks for the tyvek ground-cloth and 4 - 6 .5oz tent pegs and associated paracord tie-outs, you can get your total wieght under 5 pounds and it will still all lfit into the Surplus butt pack. OTOH, if youj pack it like these ready-kits you could have the roll over the outside of the butt-pack and some clothes and rations inside and be GTG at a grab.