Closing slam on seal

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tghhs
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Specialist
Posts: 176
Joined: Wed Dec 31, 2008 11:01 pm

Mon Sep 28, 2009 6:31 pm

Hey people,

So i just finished my coxial (i'll post it when it's working) it's 1/4inch barral and 40mm pn 12 chamber.

my problem is that when i pressurize, the piston slamms extreamly hard against the barral, which is pushing it through the front cap. This is caused because when it fires the piston moves back into the slightly smaller diameter of the pipe in the end cap, creating a seal and jammed. So in order for me to close the piston i need the same amout of pressure that my last shot had.

I normally use it at 100 psi so; 2*pi*.728 (area of piston face) = 4.571 inch squared.
4.571*100psi = 457.1 pounds of force (not caculating weight of piston)

this force is just stripping the epoxy from the sanded barral to the end cap, What can i use/make that would solve this?