Semi-auto firing mechanism

[BramR]

Hi!

I am working on a semi-automatic pneumatic gun for some time now and i need help with designing the semi-auto loading system.
I did some research and i found several ways to achieve semi auto, still i'm not sure what a reliable and effective way is to construct such a mechanism. I have an old fire extuingisher as a tank. I use a qev and a slide valve for achieving semi auto firing. can someone help me out please?:D
I am willing to pay somewhere about 30 euro's for it, depends on the reliability.

BramR, Netherlands

[jrrdw]

Hello and welcome to Spudfiles. Hang onto your money this is a free to use forum. Helping others with their cannons in return is the return...Know what I mean. You can search the Wiki as well the button is at the top of the page.

[BramR]

Maybe i wasnt completely clear. i am not paying for advice i was just naming the amount of money i am willing to spend on the mechanism. not sure if it is a acceptable amount though.

[matti]

Hello, I don't think there is a "normal" way of doing it. But sure there are some semi-auto guns here that you can look for help/guide to design your own mechanism.. It all depends on the tools, parts, size and projectiles

[POLAND_SPUD]

Consider QEV + 3way valve + air cylinder combo >>> http://www.spudfiles.com/pneumatic-cann ... 20259.html

[Brian the brain]

A QEV and a hammervalve are a good base for a semi.

In a similar way I made here, but QEV and hammervalve replacing a counterbalanced hammervalve.
The basic function would be the same:
http://www.spudfiles.com/pneumatic-cann ... 93-45.html




It could be made from standard fittings and minimal custom parts...

[bravootome]

[quote="Brian the brain"]A QEV and a hammervalve are a good base for a semi.

In a similar way I made here, but QEV and hammervalve replacing a counterbalanced hammervalve.
The basic function would be the same:


or he can use a push of a button and a a 2nd valve to shut the air of the pilot, instead of the hammer and this way it is "more" semiautomatic cause there is no need to cock the hammer, only push and fire, push and fire, push and fire.....
or make the hammer cock itself.....

[Brian the brain]

With what I suggest, the exhausted gas from the hammervalve is used to drive the hammer and bolt back.
The ammo is long gone before the breech opens..

In essence the same as in the Pnuschnikov...
Cock it once...and then pop-pop-pop.
The advantage to what I did is....the semi part can be diabled to give you full auto.
So select fire is easy..



Bram...met wat ik voorstel werkt ie als een "echt"wapen.
Dus met magazijn, doorladen en dan iedere keer dat je de trekker overhaalt 1 schot.

Als je gebruikt wat je al hebt ( wat ook werkt) maar alleen een betrouwbaar herlaadmechanisme daarvoor zoekt, dan is de blow forward bolt het simpelste.