12g CO2 conversion to 12g HPA

Hermitage10

Hermitage10

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Morning all,

I was wondering if anyone has any experience with converting their 12g CO2 powered pistols and replica rifles etc to the reusable 12g HPA bottles?

I've seen them online and at AliExpress and they seem like a good idea.....but not sure in practice how they would work in practise etc?

Any thoughts, experiences etc?
 
It won't be consistent, co2 "self regulates" due to staying liquid above a certain pressure, and will tend to be fairly consistent, whereas air will reduce in pressure with each shot
 
A 12g CO2 cartridge filled with air would only be good for a shot or two.
CO2 is stored as a liquid which produces a much larger volume of gas as the gun is fired.
 
nikvanorton said:
A 12g CO2 cartridge filled with air would only be good for a shot or two.
CO2 is stored as a liquid which produces a much larger volume of gas as the gun is fired.
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ahhhhhhhh.......good point! Knew Co2 was stored as a liquid, but didn't realise you'd only get a couple of shots from a 12g HPA.....Thought you's get a similar shot count🤦‍♂️ Wouldn't be worthwhile!
 
Masterdave said:
It won't be consistent, co2 "self regulates" due to staying liquid above a certain pressure, and will tend to be fairly consistent, whereas air will reduce in pressure with each shot
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Yeah!!!!! Hance regulators etc on HPA bottles - I haven't thought this through have I!!!!! 😂
 
If you want to use liquid oxygen, you'll have to cool it to about -200 degrees farenheight, or pressurise it to about 500,000 psi at room temperature. Personally, I'd stick with CO2 😂
 
Oxygen and airguns is a bad mix.
May have been said in jest but someone will no doubt try it .

DONT try it.

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oxygenbf.webp
 
Isn't this also illegal depending on model, CO2 semi-auto replicas being legal cos they're NOT using air? I recall this being discussed previously...
 
Jester said:
Isn't this also illegal depending on model, CO2 semi-auto replicas being legal cos they're NOT using air? I recall this being discussed previously...
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Does the propellant matter , isn't it the fact that they're self indexing rather than self loading that makes them legal ?
 
Bighit said:
Oxygen and airguns is a bad mix.
May have been said in jest but someone will no doubt try it .

DONT try it.

View attachment 625873View attachment 625874View attachment 625875
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I very much doubt that, based on my post, anyone is going to try to either:
a. Cool oxygen to -200 Farenheight
b. Pressurise it to 500,000 psi

Perhaps we should add warnings to posts containing any from of humour/irony/sarcasm?

CAUTION - This Post Contains Traces of Humour.
 
The 12g reusable ones I've seen seemed to unscrew, I always assumed they were to put a dry ice pellet in and let it gas that way. I have used one of the caplet eliminators to tether a regulated bottle to a CP2, which is a simple if inelegant conversion.
 
Proton x2 was a refillable air cartridge replacement for the co2 12g cartridge.they were filled with a pump or bottle or compressor with an adapter.
 
Jester said:
Isn't this also illegal depending on model, CO2 semi-auto replicas being legal cos they're NOT using air? I recall this being discussed previously...
Click to expand...
No Idea. That's interesting though if the case
 
Fatbob 59 said:
Does the propellant matter , isn't it the fact that they're self indexing rather than self loading that makes them legal ?
Click to expand...
I think it does as some of the replicas\pistols are indeed self-loading rather than indexing as is the case with most of the 4.5mm bb ones, and are allowed specifically due to NOT using air as the propellant.
Rings a very loud bell to me, I'm sure someone with more knowledge will confirm or not.

@Hermitage10 Is it a self-loading BB replica you're considering or a self-indexing\single shot jobbie?
 
Jester said:
I think it does as some of the replicas\pistols are indeed self-loading rather than indexing as is the case with most of the 4.5mm bb ones, and are allowed specifically due to NOT using air as the propellant.
Rings a very loud bell to me, I'm sure someone with more knowledge will confirm or not.

@Hermitage10 Is it a self-loading BB replica you're considering or a self-indexing\single shot jobbie?
Jester said:
I think it does as some of the replicas\pistols are indeed self-loading rather than indexing as is the case with most of the 4.5mm bb ones, and are allowed specifically due to NOT using air as the propellant.
Rings a very loud bell to me, I'm sure someone with more knowledge will confirm or not.

@Hermitage10 Is it a self-loading BB replica you're considering or a self-indexing\single shot jobbie?
Click to expand...
BB/Pellet replicas buddy
Click to expand...
 
nikvanorton said:
I very much doubt that, based on my post, anyone is going to try to either:
a. Cool oxygen to -200 Farenheight
b. Pressurise it to 500,000 psi

Perhaps we should add warnings to posts containing any from of humour/irony/sarcasm?

CAUTION - This Post Contains Traces of Humour.
Click to expand...
There has been people in the past asking if they can use oxygen hence my post.
 
Last edited:
Hermitage10 said:
No Idea. That's interesting though if the case
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Right I think I've found it, section 5.11(a): https://assets.publishing.service.g.../attachment_data/file/143816/restrictions.pdf

Basically I believe any self-loading firearm, that is one that loads ammunition directly in the breach\chamber, needs to be under either Section 1 or Section 5 certificate etc, however "air weapons" above 1j and below 6 ftlb for pistols, have an exemption applied if they're powered by CO2. This is what allows self-loading CO2 pistols to be sold\possessed here whereas any other true semi-auto airgun that uses air is illegal here.
I think previous discussions suggested that if you convert away from CO2 to air (or any other gas) this exemption no longer applies and the gun becomes Section 5.

So if it's one that self-loading a BB directly into the barrel you really don't want to be doing it.
If it's one that fires directly from the magazine\belt ie self-indexing it might be OK but I still wouldn't want to argue it in court.

This may all be complete bollox but I think this was the gist of it the last time this subject came up.
 
Jester said:
Right I think I've found it, section 5.11(a): https://assets.publishing.service.g.../attachment_data/file/143816/restrictions.pdf

Basically I believe any self-loading firearm, that is one that loads ammunition directly in the breach\chamber, needs to be under either Section 1 or Section 5 certificate etc, however "air weapons" above 1j and below 6 ftlb for pistols, have an exemption applied if they're powered by CO2. This is what allows self-loading CO2 pistols to be sold\possessed here whereas any other true semi-auto airgun that uses air is illegal here.
I think previous discussions suggested that if you convert away from CO2 to air (or any other gas) this exemption no longer applies and the gun becomes Section 5.

So if it's one that self-loading a BB directly into the barrel you really don't want to be doing it.
If it's one that fires directly from the magazine\belt ie self-indexing it might be OK but I still wouldn't want to argue it in court.

This may all be complete bollox but I think this was the gist of it the last time this subject came up.
Click to expand...
I'll just stay away from the original idea - probably best😂🤦‍♂️
 
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