
I didn't have a barrel on it so the paper-spitball shot across the room and left a blob on the door, so I molded a chunk of 1/2in PVC to the 3/4in to 1/2in reducer to the 1/2in copper barrel so I didn't need to epoxy anything, but I later secured it with a bolt and wing-nuts/washers. It shot a dart 5 yards into my dartboard and penetrated about 1/4inch.
Maybe with a nerf dart or something I should be able to shoot it a bit farther. I wont be doing any add ons or anything. Just something to show the family I can make something that goes "Thump!" and has a good muzzle flash.
Igniter: BBQ Lighter spark igniter removed from the plastic case and shortened. I epoxyed it into a copper threaded female adapter. I think it works well and is safe

Chamber: 14 inches of 1in copper with a 3/4th inch threaded male copper adapter epoxyed on one end, and a 3/4th inch to 1/2 inch reducer.
Barrel: About 8-10 inches of 1/2in copper.
Hope you guys like it.. Alittle!