Ok I realize this might sound kinda dumb. I'm making my own Gun, but i don't know what kind of sealant to use. I have tried using hot glue in the past but that is a horrible airtight seal it breaks after a few shots or when its twisted wrong. Is epoxy any good? I really need to know the best kind of air sealant there is that is affordable for some one with a low budget. Thank you for helping