Sdr21 pvc pipe has an ID that's perfect for golf balls. I had to call around a few hardware stores to find one that carries it however (Canada). As mentioned, sabots are good but take time to make. I usually use Styrofoam cut with a hole saw that matches my barrel ID or simply rags stuffed around th...

True - I think I'm probably just being overly cautious. I'll be building soon and I'll hopefully have the results posted. Thanks very much people

Force is applied (air pressure) to the barrel and it is only held from moving forward because of the bolt. This bolt would be held via the frame and this frame is offset. This causes a moment arm and strain on the barrel

As Mr. Due stated, that does get more complicated. If both handles aren't perfectly in contact, the loading is still uneven. I may give it a try with one and see if I don't encounter any issues

On a typical bolt, the arm rotates down to about 30 degrees from straight down, so a bolt on the opposite side would be 30 degrees from straight up

The issue I see with that is the bolt not being used would be sticking upwards as you turn the opposite one down

Untitled.png I am making a bolt action mechanism and I am concerned about forces on the barrel. In most bolt actions I've seen people using a sleeve to cover a hole in the barrel. This is functional but it always leaves a large amount of dead space between the hole and valve opening point. It also ...

I'm assuming by "normal valve" you mean a ball valve? A sprinkler valve will have a faster opening time than a manually actuated ball valve thus typically delivers better results. However, a spring-loaded ball valve is quite effective and simple to construct.

If you were using the qev as intended (filling and pilotting with the P port) this issue wouldn't arise because the qev is designed to operate that way. With your set up, which is typically used for pop-off full autos, or in your case a lack of a 3 way valve I'm assuming, you have to have a way for ...

Sounds like you need to make an equalization hole in the rubber piston in the qev. Right now air can't get past the piston so it is just going straight out the exhaust. Make sure the hole is very small, on the outer skirt, and doesn't interfere with the sealing face

^ teeheehee

Simple and elegant, should operate very reliably. Great idea to have a visible reservoir so the condensation can be seen after firing and the lightweight poly-barrel just makes sense under high pressure. Keep it up!

How are you planning on hooking it up after you get the valve out?

By finding an adapter to convert to npt

Thanks, I'll definitely try tinkering with it a bit before I start using a lot of force

Hello all, I found two oxygen tanks which appear to be empty but I won't assume so. I want to use them as air storages by filling with a compressor then topping up with a stirrup pump. I was hoping someone on here has experience with these because I want to remove the fittings in the safest way poss...

It seems like the sprinkler valve top is leaking as I get past 50psi, a result of a weak top and cheap epoxy. I'm thinking one of two options... 1-lather on the rest of the epoxy I have over the top of the valve Probably worth trying even if it is a waste of epoxy 2-move the qev from the smaller can...