I'm here to present to all of you, my newest build, a (relatively) high-pressure,barrel-sealing, piston pneumatic rifle ! Now, this is my first homemade piston rifle and i'm still running into problems, to name some there're piston lube probs, exhaust ones, as my current exhaust is a 180 psi rated blowgun, wich i'm afraid to submit to more. So in future improvements, i might put some kind of spring-loaded ball-valve exhaust.
The chamber is 1" steel, the valve is a homemade 3/4" piston one. The piston is hot glue poured into a 20 mm copper pipe with grease on the inner-wall. I also put a neoprene disc on top of it with a screw that goes all-the-way to the bottom.
The gun is pressurized using a schrader valve with the inside removed, and secured with a 1/2" steel ball-valvle.
Some speed indications (not exactly accurate but give you an idea) All of these are tested at 14 bars (200 psi)
-6mm
Airsoft BB 0.25 gram : 294 m/s
Glass BB 0.16 gram : 322 m/s
Steel BB 0.88 gram : 254 m/s
Steel bolt 0.55 gram: 270m/s
Little Specs:
Chamber : 1" steel
Valve : 3/4" piston; homemade.
Barrels : 1m x 6.02 mm ; 1m x 15mm ; 40cm x 1cm ;
And i also made a video, be sure to watch it in HQ . There will be more to come when i pass my exams! until then, have fun and be safe
[youtube][/youtube]
It's just amazing XD
Liked the "spinning"can shot the best. 
