A quick and easy ammunition fix for potato guns. The range is around 100 yards, probably more. I built my gun for less than 50$. It will probably work for 2" barrels if you scale the wadding model to 200%, but I love the 1" gun I built. The file labeled wadding needs a small amount of wadding like toilet paper to seal it in, and I have not tried the snug one as the one that needs wadding works wonderfully.
As for the gun I used a 24" long 1" in diameter PVC pipe, with a 3" wide 5" long section with a coupling and screw in plug for the end of the combustion chamber, for the barrel I used an adapter. For combustion I took an electric igniter and drilled a hole in the chamber. I'll include pictures and a detailed plan for the gun later.
I am also working on a sabot shell
75% infill is what I've been using and it works wonderfully, 100% will probably work to, but I have not tried it as the 75% infill works great.