CO2 and Needle Valve

[KyleWoodall]

Wondering if it would be a bad idea to regulate co2 out of a paintball co2 cartridge(the refillable ones) with a needle valve to a chamber. Is it feesible or would it be dangerous? I think the bottles have really high pressure on them, but if I could find the fitting to take the bottle down to 1/4 or 1/8 inch, I could just open the needle valve and watch the guage on my chamber untill it had the appropriate pressure. Seems like it would work in my head, but wanted to get some expert advice...

[brother361]

ummm if you could regulate the pressure very low you should be fine
keep in mind there not made to be used in high pressures

[ammosmoke]

Erm, you might want a pressure regulator... From a paintgun or something from beveragefactory.com. Search regulator.

[grumpy]

i would sugest one of these. http://www.lowes.com/lowes/lkn?action=p ... J-6901-100

[KyleWoodall]

I like the idea of the regulator from lowes, but that is a lot of money. I was hoping the use of a needle valve would eliminate the need of a regulator.

[potatoflinger]

I like the idea of the regulator from lowes, but that is a lot of money. I was hoping the use of a needle valve would eliminate the need of a regulator.

It's probably a bad idea to not use a regulator because if you use just a needle valve, some liquid CO2 could get into your chamber, and then when you shut the valve and stop putting CO2 in the chamber, the pressure will continue to rise, which isn't good at all.

[KyleWoodall]

Thanks for the info guys...Guess I will find me a regulator...

[grumpy]

if you have any paintball shops around you check with them, people are always buying markers and upgrading . they might have one that they swapped out for someone, they will sometimes sell them cheap cause nobody wants them. just make sure it will handle co2 , not all regs can take co2. you would also need an asa to screw the tank into and then attach the reg.

[DYI]

If it weren't for the whole liquid CO₂ problem, I'd say yes. Actually, Larda uses a needle valve in place of a regulator on his 200x hybrid - just open it slightly, and wait until the SCUBA tank pressurises it to the right level, then turn it off. As long as your chamber can survive the full tank pressure, it's perfectly fine to use a needle valve in place of a regulator in this case.

[psycix]

DYI, if the chamber could take the full tank pressure, why not run it on that pressure then?

Also, it does involve a great risk if the chamber cannot handle that pressure and you are using the needle valve type of filling. A popoff is a real need, one twist too far or some other tiny mistake, and your chamber gets filled with pressures you do not want to be in it.

[DYI]

DYI, if the chamber could take the full tank pressure, why not run it on that pressure then?

Well, I'm assuming he needs a lower pressure for some reason (perhaps he doesn't want to kill his opponents in paintball?), or he wouldn't be asking how to regulate it in the first place

[KyleWoodall]

I am wanting to build a gun that can be taken out and not need a charge it with an air compressor. I have not designed the gun yet, but I believe it will need low pressure to accomplish what I need(maybe 30-50 pounds pressure in a small chamber). I plan on making a gun that has shoots a spike out and retracts back into the barrel after each shot. I am plan on using it to...aerate my lawn.....

[Hotwired]

Umm yep that's not new here or in the world of industrial tools.

Can't be much different to that, basically a pneumatic cylinder with a return spring and instead of the rod moving something it's directly used for work.

A paintball regulator could be the easiest way to get the pressure down, a real regulator at any rate, a manual valve into a chamber you only want at 50psi is not going to be a happy bunny if it ends up getting 900psi.

[KyleWoodall]

No doubt, I am trying to build it for my Dad. I doubt he will reinburse me for my troubles, So I am lax to buy an exspesive regulator. I have been searching craigslist in hope to find a cheap paintball gun that I can rob parts off of.

[psycix]

Well, I'm assuming he needs a lower pressure for some reason (perhaps he doesn't want to kill his opponents in paintball?), or he wouldn't be asking how to regulate it in the first place

Instead of dropping the pressure, reduce chamber volume then.
More efficient.
And why use a chamber material that may be overkill?
No-one is using a stainless steel chamber on a gun which is never used above 30 psi. On such pressures, it would be way more practical to build it out of pvc, its cheaper, lighter and just as safe, as long as the pvc is rated high enough.
If you are going for the heavier chamber, then make it smaller and do not regulate down that pressure.