I'm hopefully going to be starting on making a bunch of gear in which stuff sacks will be needed. In trying to figure out the size to make them. I pondered because of how I may end up transporting them. I have a thought of making a pack similar in design to the MacPac or what ever MacEntyre's pack is called where the SS will be lashed to a frame of sort. So I thought if the SS were all the equal lengths to be lashed horizontally to the pack they would have to be of differant diameters to fit the specific item. I have various left over sizes of PVC pipe. I thought I would cut the diff diameters of pipe to the length applicable for the pack. Then I could stand the various sizes of pipe on end on the floor and try to stuff the item in. When I found the best one then I could use the pipes measurments to determine the SS size. How do you all determine the SS size? I can use a tape measure or micromiter all day but don't ask me to use a formula.