Sweet. Thanks, Jack. Will probably put this first one into my MKII version of my paintball mine...

OK, finally got around to this. Here's a pic of the QEV valve disassembled. Where exactly should I make the pinhole?

I was just thinking that the easiest way to make these cheap, simple, effective and electronically triggered would be to use a hybrid design and a simple spark igniter to trigger them. Get rid of the valve all together and just put in a foil burst disk between the chamber and the paintball barrel.

I am sure you could rig up something to fire them via an arduino wireless controller with electronic solenoids. I have no idea how to do that part. Will post the QEV version after I obtain some more parts...

Thanks, Pigeon! I am now working on refinements for the MkII version.

Thanks to Jack's knowledge, I am making a lower profile version using a smaller, cheap, modded QEV as the valve. The barrel will still be the same, and the chamber likely as well, although it would be possible to make a smaller ...

Sweet. Thanks Jack. Will try it.

Thanks, Jack. That explains my problem. I had stupidly assumed it would function in approximately the same manner as the modded Orbit Watermaster valve. I do have a chamber on the A side, but I was also filling from the A side. My intended use for this was to build an under-barrel M203 style ...

By the way, I grabbed one of these regs on Ebay. Mine worked pretty well out of the box, but I couldn't regulate it down below about 160psi.

So, I was persuaded by this forum to evolve from the modded Orbit sprinkler valve to a QEV. So far, things aren't working.

I got this valve here: http://www.amazon.com/Legris-Nickel-Plated-Brass-Exhaust-Female/dp/B00ANVTNP4/ref=pd_rhf_ee_p_imgnr_4

http://ecx.images-amazon.com/images/I/51Mu7 ...

Well, yes, you may suggest that... I have tried a few different ball valves but the real problem is that all of the valves I have found all seem to have rather high friction to move the lever, which actually worsens the problem.

I have modified the blowgun trigger to improve it with a simple fix ...

Here's a video. Sorry it sucks. My phone doesn't have a wide enough angle to capture the spread...

Pics... Loading and two test fires.

OK. Finally had enough free time to get this thing tested. Pics and Video to follow. Here is what I learned:

1. The overall design works well for liquid paint, powder, or paintballs.

2. When firing paintballs, it is better to switch to a straight 2" coupling for the barrel as opposed to the 2x3 ...

So... you're saying that I built that claymore mine with a stupidly large (but still cool) sprinkler valve when I could have used a much smaller and easier to incorporate QEV for only about $10???

Why didn't anyone stop me?

Oh, wait... because I didn't actually post my plans for it before building ...

Glad to hear you got it working. I might pick up one of those as well for another project. I would suggest that you absolutely use a remote line for your CO2 tank attachment to that regulator as it will give plenty of expansion space to prevent liquid CO2 entering the regulator and throwing it off ...