Help With making a coaxle pistion seal. Update, New pictures

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Joined: Tue Jan 15, 2008 4:51 pm

Fri Dec 18, 2009 11:17 am

Well I had a set back today. I decided to do a higher pressure shot since my neighbor was at work. I took the gun with the new piston up to 80 PSI. The piston was holding perfectly, I shot it and it was impressive to say the least. After shooting it I decided to take the piston out to lube it up with some lithium grease. I started to remove the screws that hold the bushing at the back of the gun. When I got to the last one I started to hear a hiss. Keep in mind the firing and filling assembly was disconnected at the union so there was now way the gun had air in it. when the last screw came out the bushing came shooting off the back and it along with the back half of the piston, they hit the concrete wall with enough force to shatter the 3" cap used as my piston.

What happened was the piston is hollow and did not have equalation hole in it. The center bolt holding it all together was nylon, it broke and the pressure forced the piston apart. It is easy to fix but scarred the crap out of me.

Now I have a question when I rebuild it I am thinking of drilling a series of 1/2" holes behind the sealing face where it slants to were the O-ring is. basically making the volume of the piston part of the chamber. Do you think it will cause any problems? This should help lighten it and keep it from blowing apart again.

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