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6mm qev design

Posted: Sun Jan 15, 2012 1:53 pm
by MessingWithStuff
So here is my design for a 6mm qev semi automatic. Its only notable difference from normal qevs guns is its use feeding nozzle piston constructed from a blow gun nozzle.

Operation:

A: Check valve is open, gas flow in, this pressurizes the gas chamber and the feeding nozzle, which is pushed forward until it makes contact with the barrel.

B: Check valve is closed, gas flows through the other outlet of QEV and flows through the holes in the feeding piston. This leads to the acceleration of the projectile. At the same time the nozzle is pushed back.

Concepts illustrated in other places:
http://www.spudfiles.com/forums/how-to- ... 14776.html
http://www.spudfiles.com/forums/semi-au ... 22363.html

Questions:
1. Do I have the concept of QEV operation understood correctly?

2. Will the Piston system work and feed 1 projectile at a time?

3. What is the best (least expensive) way to connect and regulate a 20 oz Co2 cylinder to around 150 psi?

Re: 6mm qev design

Posted: Sun Jan 15, 2012 4:27 pm
by evanmcorleytv
MessingWithStuff wrote:3. What is the best (least expensive) way to connect and regulate a 20 oz Co2 cylinder to around 150 psi?


This should do just fine. It also cones with a 3-way valve!! (slide valve)

And yes, you seem to have th "QEV thing" down. As for the piston.. I'm not sure. You may get some double feeds..

If I were you, I would go with one of my earlier loading system designs..

Image

Posted: Sun Jan 15, 2012 4:56 pm
by Gun Freak
Evan, he asked how to regulate it too. An air line does not regulate.

@Messing, you need a LPR or a Stabilizer to regulate to 150 psi.

Re: 6mm qev design

Posted: Sun Jan 15, 2012 4:57 pm
by Lockednloaded
evanmcorleytv wrote:
MessingWithStuff wrote:3. What is the best (least expensive) way to connect and regulate a 20 oz Co2 cylinder to around 150 psi?


This should do just fine. It also cones with a 3-way valve!! (slide valve)
If you expect for a remote line to regulate anything, you'd better be ready to pull shrapnel out of your body from a chamber the was meant to hold 150psi

If actually want to regulate the co2 down to a safe pressure then this is your best bet

Posted: Sun Jan 15, 2012 6:40 pm
by evanmcorleytv
Gun Freak wrote:Evan, he asked how to regulate it too. An air line does not regulate.

@Messing, you need a LPR or a Stabilizer to regulate to 150 psi.
Didn't see regulate!! All I saw was connect!! haha

Posted: Sun Jan 15, 2012 7:25 pm
by MessingWithStuff
Thanks for the responses.

I am hoping to avoid purchasing a palmers regulator due to the high price and ebay seems to have a few alternatives:

http://www.ebay.com/itm/Spyder-Paintbal ... 320wt_1270

http://www.ebay.com/itm/Aquarium-CO2-Si ... 958wt_1152

And there is a regulator for threaded co2 cartridges:

http://www.ebay.com/itm/CO2-cartridge-r ... 883wt_1139


At the cost of a couple centimeters the feeding can be improved by blocking off the BB source for a longer amount of time.

How reliable is macroline? I think I will end up using it.