http://modworks.blog...nals-guide.html
The tank and valve are a very cool design, one I have never seen before. Looking at SGNerf's pictures I believe this would be fairly easy to replicate in a homemade, except for the blue sealing part.
What you're looking at is a sealing thingy which has a catch on the stem, much like a plunger rod, but it's designed to press against that seal when at rest, and then the catch is released the blue part moves away from the tank front and towards the barrel, releasing the air. I've been thinking that blue piece is the only real challenge of replicating this. Do any of you lathe owners/users think you could fabricate something like that out of delrin?