Potential pneumatic - question

[Coodude26]

I have already made 2 pneumatics with success and now I'd like to try a pneumatic.

I'm somewhat new to these forums so I might not know all the terms that well.

I want to make a pneumatic, reload action, as shown in this diagram:
(I spent a lot of time on the diagram - hopefully it makes sense) P.S. It doesn't load right in the thumbnail, you have to click it. Sorry about that.



If you don't know what I mean by reload action, go down and read "Reload action"

I am worried that I might not have the same pressure every shot. How can I avoid this, hopefully using this same basic design?

Thanks for all your help.

RELOAD ACTION

Phase 0 - Ball valve, handle valve are closed, projectile in barrel.
phase 1 - Handle valve opened, releasing pressure from main pressure chamber into secondary pressure chamber.
Phase 2 - Handle valve closes.
Phase 3 - Ball valve opened, letting pressure out behind projectile shooting it.

[TurboSuper]

Uhh...a "handle valve" is just a different form of ball valve, and ball valves are pretty suck for pneumatics. You may want to consider using a sprinkler valve or QEV instead.

What's the purpose of two pressure chambers? Safety?

[Coodude26]

No, the point is that I could get more than one shot from a fully-loaded primary pressure chamber. Fill the secondary, close the first valve, open the second to shoot, close the second, open the first to refill, open second to shoot again.

[sandman]

so then use a sprinkler as the valve connected to the barrel and you can still achieve this

[TurboSuper]

Interesting. The only problem I can see is that your pressure will decrease each shot since the volume is increasing. The workaround would be to charge the main chamber to a high pressure, and use a pressure regulator to step it down.

[Coodude26]

But with each repressurization of the secondary pressure chamber it won't have equal pressure each shot?

[Coodude26]

Thanks turbosuper. Damn same time posts!

[TurboSuper]

You're welcome...damn not refreshing enough

[Pilgrimman]

If you really want multiple shots, and you aren't willing to use an air compressor or HPA, etc. I would suggest a backpack with as big an air reservoir as you can fit. This gun must be small caliber, or it will simply use too much air. I would think .50 would be the biggest practical bore, as the chamber must be relatively small for many shots. *looks at what he wrote* Man, that's confusing, huh?

[psycix]

The pressure WILL drop each shot. But there are ways for not having that.

You can use an high-pressure tank (way higher pressure then your gun will operate at) and a regulator to get the same power each shot.
This would proably call for a metal primairy chamber.
Or, just use a CO2 tank.

The handle valve IS a ball valve. It just has a different handle.

But do not use ball valves as valve, rather use a modded sprinkler. An easy way to get such a sprinkler, is to order one from http://www.bcarms.com

[Coodude26]

The pressure WILL drop each shot. But there are ways for not having that.

You can use an high-pressure tank (way higher pressure then your gun will operate at) and a regulator to get the same power each shot.
This would proably call for a metal primairy chamber.
Or, just use a CO2 tank.

The handle valve IS a ball valve. It just has a different handle.

But do not use ball valves as valve, rather use a modded sprinkler. An easy way to get such a sprinkler, is to order one from http://www.bcarms.com

That has been already established, thanks. Almost word-for-word.

Interesting. The only problem I can see is that your pressure will decrease each shot since the volume is increasing. The workaround would be to charge the main chamber to a high pressure, and use a pressure regulator to step it down.

so then use a sprinkler as the valve connected to the barrel and you can still achieve this