I think you've said you're still using the stock rubber cup with its conical cavity. If that's true, something very interesting may be happening vis-a-vis the resilience of the rubber cup and the compressed charge. "Interesting" as in Webley Paradigm and pistons with spring stacks interesting.
By the way, have I ever mentioned that "serendipity" is just about my favorite word in the whole wide world?
ser·en·dip·i·ty/serndipitç/Noun: The occurrence and development of events by chance in a happy or beneficial way: "a fortunate stroke of serendipity".
Steve
...just got home. Sure, I'll post a picture of the piston if you like. The piston itself is as stock as stock can be. However, how the seal meets the valve face is much different. The front half of the valve, if we should call it that, has a tapered edge to match that of the seal. Inside the seal is a pocket to allow the head of the exhaust stem to move outward (3/8" diameter). The stem will only move 2mm forward. The measurement to see how far travel is was taken by removing the trigger pack, marking the end point of the striker, then moving the striker forward via metal rod and remarking on the tube the striker end location. If the seal were to be the entire vessel for the swept volume, the created space is .008cu.in for this partiuclar seal. I do know there are some gains created within the base of the valve even though there is a nylon wsher press fitted in the 'void'. Instead of proclaiming a definate ".008cu.in volume", taking in to account the gains mentioned, the storage is more like .01 or so, putting the pressure around 5K psi. My estimate of, although a terminology error in the video (meant to say "60 pounds" not "60 foot pounds"), is seriously underestimated I feel. It is indeed diffcult to close and would not be for all. To be honest, I can't close it with one hand. The other hand is needed on the opposing side. Moving both hands together as low on the lever possible.
"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."