Here is the piston unit for testing. Mind you, this is a crude way of getting things to work. Not particularly taking a fancy to shaking the gun each end every time to get the piston out. Tried string, but is was getting hung up in the moving parts:
This is the piston seal with the cavity shown. The cavity volume is right at .0007cu.in./.011cc:
The next picture is the valve, again. This particular valve, though the same valve, has been altered at the piston side. If you can see it, there is a pronounced taper to match that of the conical shape inside the piston seal. There is a shelf the same with of the thickness around the edge of the piston to allow sealing contact:
The idea of tapering the valve face was to minimize losses between the o-rig and seal. Then, a well had to be created in the piston seal to allow clearance for the exhaust stem to pop and to act as air storage space. In addition, the well creates a more pliable piston seal wall.
"The majority of things in our lives are created by folks no smarter than the rest. Afterall, the world is comprised, and operated by C average people intellctually, academically, and morally. These people are often the great pioneers that set the precedent for what excellence should be."