Awesome, thanks for the photos. I would have never thought to use delrin but makes sense since it's durable and light weight. Even better, I still have some delrin stock left over from one of my streetbike projects. Can't wait to get the hardware!

If it's stainless it should hold up nicely, the weak link is the piston itself. Open it up and see what it looks like, if you have the benefit of CNC you can machine your own replacement pistol if the stock one is not up to it.

The body is aluminum. Will it hold up and not explode in my face? I ...

Thanks for all the info guys. I ordered a ninja slide valve 1/8 npt and a "ebay" QEV 1/2 npt. I tried to contact the maker of the high pressure qev but haven't heard back from them and I suspect they are pretty pricey or only sell in bulk. So hope this ebay qev holds up.

http://i.ebayimg.com/t ...

Cool, thanks Jack, Poland, and wyz. You guys have been really helpful. This has answered my question and more. I wanted to go longer than 24" rifled barrel if I can find one but will settle with what is available.

I guess I will have to experiment with the slide valves and cross my fingers that it ...

Which is better for a HPA qev semi-auto setup?

If my qev can handle over 3000 psi what is a realistic firing pressure? I think I've seen commerical hpa rifles that are regulated down to 1500 psi. I'm having trouble finding a slide or 3-way valve that can handle 1500 psi or higher!

Can anyone help ...

I've looked at similar valves before, but you always need to be extra careful about hydraulic valves because they're not made for air. As for your pilot valve, a paintball slide valve can handle 2000 psi pretty well in my experience

Thanks. What would be possible problems? Leaking seals or ...

Ruelco model RQ-2 1/2" NPT Hydraulic Quick Exhaust
there are different springs for various pressure ranges. Here's the link:

http://www.ruelco.com/product.php?pid=30

I don't know too much about valves, but maybe Ruelco has a valve that can be used as a pilot... if the pilot sees 2000+ psi ...

Hi all,
New to the forum and to homemade air guns. I want to build an HPA pellet rifle using a QEV. Want to test a basic setup then hopefully a semi/full auto.

I have found a HP hydraulic QEV that can handle well over 3000psi. I have some questions though:

1. does the qev chamber see all HP from ...