Blow back based design

[trollhameran]

Would it work if you had the barrel and chamber sealed by o rings rather than by welding or using compression fittings, so that when chamber moves forward, a bar will hit a hammer valve, which will fill the gun with air, then the chamber will move back, due to the pressure pushing it, exposing holes in the barrel, firing the projectile, then when the chamber is empty, a spring will move the chamber back into the beginning position, ready to start again.

It sounds complicated...and I assure you it is not really, i will try to draw up a diagram explaining it.

Edit: Ive made a diagram... Its a bit jumbled so I hope it makes sense

[MaxuS the 2nd]

Your explanation sounds just like how a Spyder Paintball Gun works.

[trollhameran]

Got a diagram of one of them you can post?

[MaxuS the 2nd]

Sure.

[trollhameran]

Thanks man, it would be similar to that, except rather than having a moving bolt, the whole chamber moves back and forward over the barrel.

[MaxuS the 2nd]

Yeah I realised the difference after reading your explanation through again.

[trollhameran]

Do you think it would work?

[MaxuS the 2nd]

Yeah it looks like it should. Although it could be tricky getting seals on all the parts. I was actually going to install something similar into one of my guns in the near future.

[trollhameran]

Cool. The way I have set it out should work with just 3 o rings between the chamber and the barrel, and the chamber would hopefully move no more than 10mm. Hopefully i will get a chance to test it soon, because if it works, it could be used for full auto, or changed to semi auto by just removing the spring, and re cocking by hand.

[Sticky_Tape]

It wouldn't be semi by recocking by hand that would ba a repeater.

[trollhameran]

Woops my mistake, well it would be easy to switch between semi and full, it would fire full auto if you held the trigger down, but if you pulled the trigger then let go, the trigger the re-catch on the chamber as it comes back.

[Sticky_Tape]

Here you go.

[trollhameran]

Oooooh a cookie

[trollhameran]

I figured if I can fit a barrel into the plunger on a syringe then it will make a perfect starting point for this design.