My Coaxial Pneumatic Launcher
This launcher took several hours of build time and design time, and also about 4 hours of lathe work. It looks kind of bad with the primer, but I had to really rush to get it pieced together before the PVC got stuck in the wrong place. It will look much better as soon as I get it painted (the breech end has some paint on it already). I learned a lot while making this gun, such as to make more complicated launchers a lathe is very handy. I think that this launcher is pretty unique for the fact that it is a coaxial gun, and also a breechloader. The 1.5" barrel actually passes through the 4" chamber. As you can see this is a pretty massive gun, but is still easily handled which was one of my design criteria. Another unique aspect of this gun is the built in ramrod, it's actually a funny story of how I came up with this idea, it just sort of popped into my mind while I was using the restroom. The built in ramrod pushes the potato up past the 1.5 inch tee, which is where the air comes into the barrel from the chamber.
I am very photogenic as you can see from this picture..... HA HA
Breech detail of built in ramrod and loading procedure