In the process of finishing a piston air rifle.... It's all glued up drying atm... should have some pics and videos up tomorrow if people are interested. Def. gonna be one heck of a BOOM!
Here is a short video I made with my phone camera... sorry for poor quality. You can not see it on the video, but there is sorta like a shock wave, that exits the barrel that you can visible see, just before the water vapor exits the end of the barrel. It is a lot louder then it sounds in the video, but the microphone was overloaded and didn't pick up the sound properly. I will be adding a silencer to it... because it really is that loud.
Here is the video as promised
If any one needs plans... or general info... I'm happy to help -Adrian
Cool video. I have made a few cannons of various sizes using sprinkler valves, not piston valves. They are still impressive though. All of them can accept barrels of different sizes (e.g. from tennis ball/ snow ball size, down to dart size). I prefer making them with breach style barrels.
Allelectronics.com sells regulated psi valves that screw onto existing valve stems. I have a couple ranging from 50psi to 90psi. You cant overfill the tank with these in place.
I have pressure gauges installed, regardless, for safety.
@ bob: what is the yellow tank for? Is it needed for a piston type setup?
Don't forget to use hearing protection! Goggles too!
@cold... The yellow tank is from an old fire extinguisher, this is the air reservoir... as the piston move back, the air rushes from the reservoir to the barrel.... an example can be seen here...
@zrtmwa tanks working pressure is rated at 115psi and the pvc is rated to 120psi... the barrel is 15mm and this is what gives it it's power... it is being reduced from 25mm down to 15mm with high air flow