Have you calculated the bolt spring force that will be necessary to open the valves? If the spring is strong enough to open the valves, I doubt that the gas from the valves will be sufficient to ever completely overcome the spring pressure and move the bolt to the forward position where it can re-engage the sear again.
why is that?, the spring will never have to directly push against the force of the hp tank, what I didn't include in the animation was the springs which are pushing the valves shut, the inertia of the spring will be enough to open the valve and keep it open as long as the air pressure hasn't reached pop-off level. once the bolt starts shooting backwards the inertia should be enough to get it too trigger latch point, if not then I will change the location of the trigger sear so it does not have to go so far. hope that has explained that.
Also heres another thing, good luck machining it all. Its going to take at least 1 month to get the firing mechanism made, and maybe 2 to get it designed to where its easy to machine. I am no machinist, so I cant say how long it will really take, but it will take awhile to build. And no doubt cost alot.
Machining this is no issue, the entire point of the straight line valve was to make it easily constructible, a steel tube a thick bit of flat sheet metal a few tubes and shit loads of epoxy should make this in a treat, the cost on the other hand is no issue I have a fair bit of funds and this is a long term progect.
If you can make it, I think it should work. The hammer valves should prevent it from hanging. Unless you use HPA though, I wouldn't expect great performance, maybe 400 fps for 0.20g airsoft BBs with propane, but if you want it for skirmishing that's perfect.
You're wasting a lot of air cycling the mechanism which is quite high volume, there are more efficient ways of designing it, definitely it would be worth using a single valve - 50% less things to go wrong.
Agreeably the real valve has been carefully worked out to have optimum power for the blow forward chamber, also 400 fps is what I was aiming for as I wish to use this for skirmishing.
Otherwise in my opinion the two valves would increase the performance of the gun, of course there is more to go wrong but if carefully made I think this might stand a good chance of greatly improving performance.
The prototype of the valve is coming as soon as I can get an empty large propane tank for an air chamber, as I have no air compressor decent enough to provide a constant stream of air.
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