Plastic hull 37mm

thingiverse

This is version 2 of my 37mm round to be used with a plastic 37mm hull, a minimum wall of 3 layers is needed. Loading with 30-45gr of FFFG will get about 100meter range with the projectile filled with 100grams of sand. For the pusher and bushing adding a single support in the middle works out the best in my testing. The nose cone can be printed with no supports but I suggest a brim to keep it stuck on the build plate. To finish the round you need to hot glue a 35mm wooden plug to the bottom of the pusher or else the round will be ripped around on launch. The bushing will need to be aligned and pushed down as it should be a snug fit to prevent gas from going around the bushing. Also please check that the projectile fits in your barrel as it is designed to reduce any gas blow by.