The valve shown on this page is taken from a Crosman 2200 Magnum.
This is a multi-pump rifle that is pumped about 10 times to fill the valve to pressure.
The hammer is cocked back and when the trigger is pulled, the weight of the hammer strikes
the valve stem which releases the pressurized air. The air rushes through a small
opening in the valve that connects to the barrel. I have tried to pump the rifle 20
times and test the FPS. It makes no difference as the valve can only handle so
much volume of compressed air.
End cap and both plastic seals. Spring seals both ends.