QEV modding and pilot/tank filling

[AlfiePB IanB]

I got myself a couple of new QEVs (Humphries QE2 and QE4 iirc) due to reading positive comments. I am just going to set them up with a slide valve and tank to test their capabilities.

I have been trying to find out what the benefits/disadvantages of modding a qev via spring and small to chamber fill rather than pilot filling. Can someone with experience explain the advantages of chamber filling and when it would be beneficial? How do you set it up so that when the qev is activated the air refilling the chamber is not just lost out the barrel.


Eventually my aim is to use the 1/4" qev to pilot the larger qev, does anyone have an experience of this and would the qevs need to be standard? It will be used for a high pressure single shot 15mm or 12mm most likely gun.

Thanks in advance, Ian