Small Coax Pilot Problem

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tony48
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Mon May 23, 2011 8:23 am

Thank you very much for the info. I think I will be able to find o-rings at a local hardware store. If I do use an o-ring on the piston then I will be worried that there wil be too much friction and the force required to push re piston back won't be created by the small difference in piston and barrel size. That is my only concern and i think it will be alright especially if I use a check valve of some sort.
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Technician1002
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Mon May 23, 2011 9:56 am

Getting the valve closed is one of the reasons I improved a piston valve. It is a little harder to build.
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tony48
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Fri May 27, 2011 5:13 pm

For anyone interested, I painted the piston to reduce blowby and got it to fire with the blowgun trigger although it is finicky. Here are some picture of the gun and trigger. The air hose it attached to the pilot area via a 1/8" by 1/4" barbed fitting. The hole was drilled and tapped and airtight. It will be posted eventually in the showcase when I get some damage pictures and get it to trigger more reliably. It's pretty comfy to fire. The rear fill valve acts as a stock and I hold it like a normal rifle with my right hand on the trigger and left on the chamber.

Grip assembly:
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the unit
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Fri May 27, 2011 8:03 pm

Your pilot volume is probably hurting performance as well. Why not place the blowgun where the ballvalve is and use a trigger linkage, and then put the ballvalve where the hosebarb is.
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saefroch
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Fri May 27, 2011 8:15 pm

Agree with the above. Pilot volume is pretty large...
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tony48
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Fri May 27, 2011 8:31 pm

the unit wrote:Your pilot volume is probably hurting performance as well. Why not place the blowgun where the ballvalve is and use a trigger linkage, and then put the ballvalve where the hosebarb is.
I know the pilot volume is huge but I wanted it to be triggered from a blowgun from the place it is currently located.

What is a trigger linkage?
If life gives you lemons, put them in your cannon and shoot them back at life!
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