Author Topic: Anyone built their own PCP  (Read 1052 times)

Offline DonTMN

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Anyone built their own PCP
« on: September 28, 2009, 02:22:04 AM »
I would like to converse with someone off the board that has built their own PCP or is intimately familiar with them.  

I built one of buckleys and everything functions fine with one exception,  I cannot get above 690fps using crossman premier pellets..  Got a few extra holes in it but what the heck it's a proto type and my first build..  

Here are the particulars:
.22 Caliber
20" barrel (lothar walther choked)
JDSairmans 13 cu. inch tank which has been filled as high as 2,500psi
Regulator on tank is 1,600psi

Right now I have a spring behind the striker that is as strong as I can use and still be able to cock it.  It is a 2.75" long with .047 dia. wire.

If I use a piece of rod and hammer I can get good penetration with the pellet but not with the striker arrangement.  I cannot go any heavier on the spring

I know I am not having an air leakage issue as everything is o-ringed.  Since I was going to .22 and the plans were for a .177 I figured I would need more air and upped the port sizes a bit.  Is it possible I am too big on these and in doing so I don't have enough air flow with the length of time the valve is open?  I had to set the tank back a bit so where it screws on give it a fairly large reserve chamber so the volume of air should be adequate.

Anyhow if you have any idea I am all ears.. If you know of another forum I can try that is a little more into building PCP's I would be happy to do that also.  I wanted to build a large bore PCP but NOT till I get this issue solved..

Thanks Much...

DonTMN