This is a quick, side project to my (undisclosed) main project. It utilises the extremely powerful sprinkler valve, mine was a irritrol 1" one. I expoxied in a blowgun, and was staggered by the performance. It works much better without the spring, and is noticably louder.
Features an ACOG sight, from an old bb gun (Cybergun Famas)
Breach loading
Rifled Barrel (OMG!)
.75" Barrel , 2" Chamber
and a handle over the blowgun (1.5" DWV)
Everything is 8 Bar pressure rated.
PICS!
P.S, Im from the UK, so sprinkler valves are pretty rare.