Convert a Gas refill cylinder to an air cylinder?

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Airgunloverboy265
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Sun Apr 24, 2022 9:58 pm

Hey guy's long time. anyways I have a question. You guys know about these gas refill cans for Gas blowbacks ? https://www.alibaba.com/product-detail/ ... 62711.html

Well i was wondering, if i took an empty green gas can and stuck one of these Schrader valves https://en.wikipedia.org/wiki/Schrader_valve at the end replacing the Green gas with air, will it work? Cause I figured that it'll function kind of like a hpa gun and unlike a gas blowback can this modified aircan can be refilled without spending money on another green gas can for your blowback airsoft gun.

Also a little off topic, does anyone know how to change your username? Cause I plan on renaming my spudfile username with my upcoming youtube name but when i go to the edit page of my profile it won't let me change my name.
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Mon Apr 25, 2022 5:36 am

The trick to using that can for a reservoir will be getting the schrader valve locked into it with no leaks. Contact PCGUY at Spud Files email: admin@spudfiles.com about changing your user name.
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mrfoo
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Tue Apr 26, 2022 11:25 am

At a guess, that can's gonna be super thin, which would make modding it pretty difficult. I'd be more tempted to look at a discarded 60l oxygen canister or maybe a fire extinguisher CO2 recharge canister. Rather than modifying a canister, try talking to a local machinist, see if they can make up a tee mating the bottle thread / cas release, a Schrader for filling, and whatever you need for output to the cannon.

Thinking about it, IIRC MAPP canisters have a gas outlet and a schrader valve (that you're absolutely not supposed to use).
Airgunloverboy265
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Tue Apr 26, 2022 6:59 pm

mrfoo wrote:
Tue Apr 26, 2022 11:25 am
At a guess, that can's gonna be super thin, which would make modding it pretty difficult. I'd be more tempted to look at a discarded 60l oxygen canister or maybe a fire extinguisher CO2 recharge canister. Rather than modifying a canister, try talking to a local machinist, see if they can make up a tee mating the bottle thread / cas release, a Schrader for filling, and whatever you need for output to the cannon.

Thinking about it, IIRC MAPP canisters have a gas outlet and a schrader valve (that you're absolutely not supposed to use).
What I meant was I'd drill a hole at the end of the gas canister and then epoxy on the Schrader valve in the end for it to accept air instead of gas. But your saying that it's impossible?
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farcticox1
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Wed Apr 27, 2022 5:09 am

I'd go with an old fire extinguisher if size is not an issue, I have one on my full auto vortex, I think it is rated for 450psi and there is a nice brass block on top to get a fitting in
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Wed Apr 27, 2022 6:52 am

Airgunloverboy265 wrote:
Tue Apr 26, 2022 6:59 pm
What I meant was I'd drill a hole at the end of the gas canister and then epoxy on the Schrader valve in the end for it to accept air instead of gas. But your saying that it's impossible?
Nothing's impossible. But at a guess, the walls of that canister are no thicker than 0.5 mm or so. That's super thin, difficult to drill, and difficult to get any kind of seal on. Remember, if you're trying to keep pressure in, you need to have something to stop the valve coming out, and that's gonna be really difficult to do without access to the inside of the canister. Sure, you can go buy an automotive schrader valve, but they pull through the rims from the inside, something you're not going to be able to do. About the best you could probably do would be to braze on a schrader stem, but still, with nothing to screw into or key onto, I doubt it would hold under any serious pressure.

However, the canister does have a valve, and it's not one way - after all, they had to have some way to fill the damn thing with gas, right? So you need a fitting that can hold the valve open whilst sealing against the can, and which has a schrader valve or other fitting permitting you to push air into the canister. No pissing about modifying the canister with doubtful results, and hell, you can have more than one of them charged and ready to go. But you'd need to know what the fitting is, and bear in mind it's designed to be single use, so it probably isn't going to stand up to multiple uses very well.
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Thu Apr 28, 2022 4:22 pm

You can adapt this way. If you use only one one-way valve for charging and exhaust, one end of the long inner tube must be perfectly capped and secured. You can assemble everything outside, and then seal the inner tube with epoxy. In my opinion, if you secure the valve well with a pin, it is safer that way.
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Airgunloverboy265
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Thu Apr 28, 2022 7:14 pm

farcticox1 wrote:
Wed Apr 27, 2022 5:09 am
I'd go with an old fire extinguisher if size is not an issue, I have one on my full auto vortex, I think it is rated for 450psi and there is a nice brass block on top to get a fitting in
GUEST_0a7c7aa0-6c34-45b5-ace2-0a2ed00b17dd.jpg
Will it work on a commercial blowback too with some modifying of course?
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