pneumatic repeater sidearm

[inonickname]

Admittedly, it was inspired by JSR's blow forward breech (and his numerous other designs). That could work for building a pistol.

[psycix]

Well, you did make a blow-forward part there. But it does not move any bolt.
What is the function of your collar there?

[Hotwired]

It'll interrupt the flow giving bursts of gas.

Its likely to cycle very fast however (thousands of cycles per minute with such a small moving part) and that won't necessarily translate to a faster rate of fire.

[scavies]

Sir, to make this, you would need infinite patience, but could I request that you find your way to a CNC machine at an institution?

Maybe you want to use a design similar to a recoil operated paintball gun. Always good to take advantage of newton's second law...(is that right?)

[IA_Armourer]

Im thinking of scaling it up to the size of a rifle.

is anyone else thinking M1 Garand.

I am

[sputnick]

wow, not just "inspired" so much as copied, and as much as I hate to admit it, that was one of my least favorite of JSR's inventions, because as soon as the plunger pushes back past the hole in the pipe, air is just sitting there acting as a cushion until enough air escapes through the cracks and it slides back. Make it smaller, his was F-ing huge for basically nothing. Use the little device he had in his (almost) auto, the more recent one. and this kind of idea only applies to bb's, you can try with stuff like paintballs, but it will be shit with the flow from a blowgun, especially with the dead space in your mech. there.

And I agree with everyone else, you need a bolt, otherwise the ammo will just all roll into your gun, then you have a one shot spray gun.