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Airsoft gases and external gas rigs

25598 Views 42 Replies 20 Participants Last post by  ManicMechanic
Hey everyone, I am going to talk about Airsoft gas and external gas rigs.

Lately I have seen a number of questions related to gas guns here and outside of the internet. So I am going to put this together in hopes that it helps everyone understand gas and external rigs a little bit better, and educate those that don't know squat about gas.

Lets start off with what gases are in use. I am going to start off with the lowest pressure and go up.

HFC134A (R134A), Duster Gas (HFC152A, HFC143A, HFC134A) - These are "low pressure" gases designed to run in plastic slide pistols. 134a: [email protected] 30c/86f=96.99

HFC22, Green Gas, Top gas, Propane - These are the most common gas in airsoft currently. Most notable is the green gas and propane. Propane: [email protected] 30c/86f=141.77

Yellow gas (MAPP, MAP//Pro, Proplylene) - MAPP gas, Discontinued as of April 30, 2008. MAP//Pro and Propylene (which are the same). Proplylene: [email protected] 30c/86f=174.54

Red Gas and Black Gas - These 2 I dont have any data for as I can not find much on them. From what I have found out is that red gas is quite a bit stronger then green gas. Black gas is apparently even stronger then red, supposedly anyway. From what I have gathered with the addition of CO2 and HPA into the sport, these two for the most part have been phased out.

Addition: Well I thought it was phased out...

Red Gas-
According to wikipedia, red gas is HCFC-22, and it seems to be illegal in some places(US).

The pressure of red gas(HCFC-22) is about 132 PSI.
Propane, which is the main ingredient in green gas, is about 124 PSI(Green gas is a bit weaker then propane, as it's a mixture).
And propane has been known to be too much for some guns.

You made me look something up, and I learned something new... Shame on you!

Edit: It might be alright, if the weather is very cold.
But the consequence, of leaving it in the gun in room temperature, is a unknowen factor, as it depends on your gun being able to handle the pressure.
CO2 - This gas is the next most common gas in airsoft. It is a very versatile gas. It powers pistols, grenades, rifles, and more. CO2 has an output pressure between 800-1200psi depending on temperature. 1200 is when the designed safety devices fail and vent the gas in order to insure no catastrophic vessel failures occur. In other words it keeps the canister from exploding.
CO2 comes in a variety of containers, ranging from 8gram cartridges up to 50 lbs cylinders (which weigh approx 200lbs). This gas is also cheap.

Thus far all of the gases I have listed are all liquid gases. I refer to these as "dirty" gases. I will explain why.

Source: Gas duster - Wikipedia, the free encyclopedia
When the top is pressed down to open the valve, gas flows out through the nozzle. The pressure inside the can therefore drops, and is no longer sufficient to keep the contents as a liquid; so some of the liquid boils, until the equilibrium pressure is re-established. The vaporization of a liquid is endothermic; thus, heat is absorbed, the temperature can reach −50 °C (−58°F), and the can becomes cold.
Continued use over a short period of time results in the reduction of the can's temperature. As the temperature drops, the vapor pressure of the liquid also drops, resulting in decreasing force of the gas at the nozzle. When the force of the ejected gas at the nozzle is insufficient to accomplish anything useful in terms of dust removal, and the temperature of the can reaches the boiling point of the liquid (that is −25 °C (−13 °F) for difluoroethane), the liquid no longer evaporates into gas in any useful quantity. The can must then return to room temperature before it will again provide sufficient gas flow. Alternating between two cans (allowing one to warm while the other is being used) is one way to work around this problem during an extensive dusting job. Warming the can with a heat source can be dangerous as the can may overheat and explode.
A related category of product has an internal dip tube that reaches to the bottom of the can, so it sprays the liquid. It evaporates very quickly, chilling items it touches in the manner that dry ice (solid CO2) would. These "chill spray" cans are used to troubleshoot malfunctioning electronic equipment.

This is referred to as Cooldown. All liquid gases do this.

I hate liquid gases, the reason is because of the endothermic reaction. This has destroyed more orings and seals in my paintball equipment then I care to calculate. The same thing happens in airsoft gear as well.

The last gas I have for this list is HPA, or High Pressure Air. As far as consistency goes, all gas guns that are not powered by HPA are unregulated. Which means the pressure of the gas going into the barrel is what ever. Which gives you massive jumps in FPS.

HPA needs regulation. Seeing as it is just compressed air in a bottle at high pressure (3000-5000 psi depending on tank.) All tanks used in airsoft are paintball tanks which have a regulator to bring the output of the tank to 850psi, or 450psi if you get one with a Low Pressure reg on it. HPA is not affected by cool down as it is not a liquid, it is also not affected by ambient temperature.

Most tanks come in 2 pressures 3000 and 4500psi. There are others but those are rare. Tanks also come in a variety of sizes as well as pressure. The size is in Cubic Inches, or CI. Sizes range from 13ci to the massive 144ci. Clearly the larger the ci the bigger the tank is.

Addition: You remember how I said that liquid gases were "dirty" well HPA can be dirty as well. Literally dirty, as in dirt and dust. Some fields have compressors that do not have filters, which allows for dirt and such to enter the tank. Something to keep in mind should your P* act up when you filled your tank from a dusty, dirty field.

A note on HPA tanks. All HPA tanks need to be re-certified every few years. For the aluminum tanks (also known as "steelies" due to their weight) is every 3 years. While the fiber wrapped tanks are every 3-5 years. This is merely a general rule of thumb, you need to check on your tank the exact details for hydrotesting. Addition: Examples of hydrotested tanks.

Also make sure they have the proper markings for your country, US D.O.T stamped, EU PI stamped, everywhere else I think is TC stamped.


When paired with a good regulator or 2. You can lower the pressure down to 60-135psi, the pressures that are used in most high end paintball guns and p* systems. I will get into this next.

Ok. Now its time to get into Regulators.

How does a regulator work? Here is the answer.

Source: Regulators Explained:

In today's high-tech world of paintball, almost all of us use a pressure regulator of one kind or another. One of the first in the industry was, of course, the AIR valve in the Automag, introduced almost a decade ago. Now, we have multi-stage "pressure balanced" HP nitrogen systems, inline regulators, more paintguns have regs as part of the operating system... the list is endless.

So how do they work?

First off, in the very basic design, the pressure regulator is essentially a spring-loaded check valve. Fig. 1 shows a simple, basic regulator. This design is used, in one shape or another, in the Automag line, Air America's HPA systems such as the Raptor and Apocalypse, and even the ANS 'JackHammer' pneumatics reg for the Autococker, among several other applications.

Fig. 2 shows an RG-1 type reg design. The concepts are essentially the same, but for simplicity's sake, the majority of this article will be in reference to the fig. 1 system.

In this example, lets start with the 'adjuster' backed off, so there is no tension on the 'reg piston'. What is happening here is, the high pressure (supply) air is pushing the 'reg seat' against the 'seal'. This seals the HP air from escaping, and probably getting into trouble somewhere.
This seal is made, because the 'supply' air is at a higher pressure than the 'output' air, which keeps the seal shut. So now, we crank down on the 'adjuster', which begins to put mechanical pressure on the 'reg seat'. However, the 'supply' pressure is still greater than the spring pressure against the 'seat', so it remains closed.
But if we keep cranking down on the spring, eventually the spring tension will overcome the 'supply' pressure, and force the seal open. So now, air is allowed to flow between the 'seat' and the 'seal', and begins to fill up (pressurize) the 'downstream' side of the reg. (Toward the gun, assuming nothing leaks.) At a certain point, because the 'reg piston' is in a sealed area on the 'low' pressure side of the reg, the additional pressure in the downstream side also begins to push on the reg piston, helping the supply air pressure force the reg seat closed.

This is the tricky part. Assume the 'supply' air is X psi. Assume the output (or downstream) side rests at less-then-X psi. Once you start cranking down on the 'adjuster', the spring pressure on the 'reg piston' gradually forces the 'seat' open, allowing the 'supply' pressure to flow to the 'output' side. This begins to pressurize the output side, which in turn begins to push against the 'reg piston' against the force of the spring. At some point, the supply pressure against the 'reg seat' and the pressure against the 'reg piston' from the output side overcome the spring's pressure and force the seat closed again. At this point, everything is in a state of balance.

Now, do something stupid like fire the paintgun or crank down on the adjuster harder, and things happen all over again.

When you fire the paintgun, that reduces the pressure in the 'output' side of the reg, so that the spring tension can again force the 'reg seat' open. This allows a small burst of air back into the output side, and as soon as pressures equalize again, the reg seat closes. (This is known as "recovery" and faster recovery is better, to prevent velocity drop during rapid fire.)

Or, in the other example, you crank down on the adjuster, which adds spring pressure which forces open the 'reg seat' again. And again, the seal allows a small volume of air through, and as soon as pressures equalize again (This time at a higher pressure) the 'reg seat' closes again.

The action of the reg seat opening a fraction of an inch and repressurizing the output side happens each and every time you fire the paintgun or alter the velocity. The reg could also be having to constantly work very slightly if your system leaks, as it tries to maintain downstream pressure.

Now, this is a very simple, basic description of how a regulator works. There are a lot of other factors to consider, such as how the loss of the 'supply' side pressure can increase the output pressure. Once the tank pressure drops, it becomes easier for the spring to push the seat open,and
that's the equivalent to increasing the spring pressure, so the output pressure rises, even though the adjustment is unchanged. Also, as most 'Mag owners will testify, the condition of the reg seal can become critical; if the seal/seat leaks, there is nothing to stop the full tank pressure from passing through to the rest of the gun. A dangerous situation in some cases. (That's why HPA systems have burst discs on the output side.)

There are quite a few different designs of regs in Paintball, though most can be classified as one of two types: The most common type has the adjuster vary the tension on a spring, which acts on a reg piston and seat, against a fixed reg seal. This design is used in UniRegs and Automags, among others.
The other design has the adjuster press directly against the reg piston and movable reg seal, which acts against a "fixed" spring pack. This is the basic design of the RG-1, Angel foregrip reg and WGP reg.

There is, of course, far more to pressure regulator technology than this little article can hope to cover. But the basics are here, and hopefully, this will help you to better understand the inner workings of most regulators.

Ok, now that that you know how they work you should understand why they are a big deal.

I use the term Recharge instead of Recovery. When looking around for a good regulator setup Recharge rate is important. Mostly for those with P* systems and the like. As Doc said, the better the recharge rate the better the reg. This is true, but it is not as vital in a sniper rifle, but if you use your rig for different systems then it will be.

Now as far as setups go, dual regulator setups are generally better for sniper setups then single reg setups. Especially with CO2. Dual regs allow you to "dial in" your fps better then a single. They also do a better job regulating the airflow over a single. On average, of all the signle reg setups I have seen and worked on I see an average FPS difference from shot to shot of about 5-7 fps.

Most dual regs I have seen and worked on have a FPS difference of maybe 1 fps at most, in one case 5 fps due to old grease and gunk buildup.

From my experience, some will argue this but I know this as fact, all regulators have a break-in period. The actual amount of time for this break-in varies from reg to reg and brand to brand. There are far too many factors to account for when dealing with break-in time so I am not going to get into that. DO NOT ASK ME "How long will it take to break-in BLAH reg?" I AM GOING TO IGNORE YOU. Just getting that out of the way.

Now most regs were built for HPA in mind, not CO2. Just be warned that not all regs handle CO2 well. All of Palmer's Pursuit regs will handle CO2 just fine for the most part, may need more maintenance ever so often, but that comes with the territory of using CO2.

Not all regs are maintainable. These are normally the cheap ones. Make sure you buy a reg that is rebuildable. This will keep you from having to replace your reg every time they break. Yes regs do break down from time to time. Most rebuild kits are cheap compared to the price of a new reg.

I will add more to it later, for now I am going to go get more burn cream...
Let me know what else you guys want to know, I will add it to this.
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So you are wanting to convert your KJW. Well there are a few things you will need to look at first.
What gas are you going to use? HPA or CO2 capsules?
A few things you need to consider prior to picking your gas is:
Play style- How much do you shoot? A lot, a little?
Availability- Not all places fill HPA tanks, the closest place that fills them could be an hour+ away from you. While you can grab 12gs from your Walmart, 2 min from your house.
Positioning/Mounting- Where are you keepingyour gas system? on your back? in a rifle stock pouch? In your butt... stock? (lol, sorry couldn't resist.)

Is that everything? No, those were just some of the more important things I came up with. There are others but we will cover those when we get to them.

Either way you will need a regulator. As I said above, not all regulators handle CO2 well.


We are going to start with CO2, as it is the easiest with only 1 good option. Palmer's Pursuit Shop. They make THE BEST CO2 regulators. Are there other options? Probably, are they as good? Doubtful. The performance of their regulators are almost legandary, and are considered the gold standard for co2 powered paintball.

A Pamler's reg with a CCI quick change adapter is pretty much all you need. I will list some example setups later on.

Let's move on to HPA...
This may get a little confusing for some of you, but I will have some example setups later and explain why I chose the parts.

First lets start off with what you should not buy, this: BUILD-A-RIG - Amped SLP Air Rig

These were built for hobby/home shop air compressors. These also require you to use a SLP tank regulator. The reg is only $20, this should be a massive red flag right there. Why would you spend the money on high end barrels and buckings and what not just to skimp out on one of the most important things that will dictate how good or piss poor your shots are going to be? It just does not make sense to me why you would.

For those of you that have made this dumb choice, fear not! We can fix your uninformed choice for your air regulation needs! Luckly it will not be too expensive to fix. Well... It can be, but you have a good majority of the parts you will need already from your existing setup.

I'll come back to this later, for now we are going to move on to better options.

I have stated that the Palmer's regs are not the greatest on HPA as there are better options, but they will perform well enough. You can clean up the Palmer's by using a Dual Regulator setup.

Some other options are the Ninja LPR/Firebase, Dye, CP, and AKA. The last 3 you will need to assemble the rig your self. We will get to that later.

Ninja Paintball, they make some stellar gear and they have been doing so for just as long as Palmer's Pursuit. Also FYI Ninja builds the Firebase for Redline as a private label item, if you rip them apart they are almost the exact same.

The Dye Hyper3 is a pretty good reg as well as the CP regs, AKA 2-liter+ and the SST are solid performers as well.

Tank regulators:

The tank regulator is also important, not as quite as much as the main regulators I mentioned above, but you can squeeze a little bit more performance out of your setup if you pay attention!

Ninja is going to spotlight this section too. The Pro V2 tank valve is a pretty hardcore line. Fully rebuildable, and you can adjust the air pressure coming out of the tank to some extent. They sell additional bonnets in case you damage the one you have. Which you probably will. I have not used the Pro V2 yet, I will pick one up at some point and compare it to the Dye Throttle I have.

The Dye Throttle tanks are also quite good. Excellent airflow. Not rebuildable or adjustable. (to my knowledge)

CP used to be top dog for a while, but are still a good tank reg.

I am just going to say this now, just go with the Ninja tank reg. Just get the standard Pro V2, NOT THE SLP OR SHP.

Here are the owner's manual, the addendum to the owner's manual, Installation guide, fill valve assembly replacement guide, and the burst disk replacement guide.

For those with an SLP you can buy a new tank reg and replace it if you wish.
Here is a link, Ninja Paintball Pro V2 Regulator - 4500 psi - 450-800 psi Adjustable Output - Lowest Price Available from


Ok now for the section everybody is waiting for! THE EXAMPLES!! YAY!! All hardware is 1/8 NPT, I will not add the hardware unless needed, lists will get too long and junky. These are things I would do and recommend people.

Notes: P* run with the Foster 2 Series couplers. ASA threads are .825x14


Ex.1: In stock installation, or external rifle stock pouch. Basic build.

KJW marco line kit

CCI 12g quick change

Ex.2: Advanced build.

12g CART regulator

PPS ASA to 1/8 NPT

1/8 NPT female coupler


Ex.3: Hardcore

This is the rig I am more then likely going to run or something very close to it, myself when I get my gas rifle. This is designed for both CO2 and HPA.

Female Stabilizer


1/8 NPT ball valve

CCI 12g adapter


Plus connectors and other bits.

I will come back and finish the HPA section in a bit, I am really tired and spent all weekend looking up info for this. Enjoy what I have done so far. :shot:
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Brain went poof. And I'm a rocket scientist in the making. I will take some more time later to read it and understand it, when I'm not tired. Looks good out of what I read.

Maybe you can help out the other airhead(geograd ;), hopefully you two get the joke and aren't offended) with his new system.
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You offend me to the core Hunter, I hate you so much...

kidding! :D
..quick skim of your post, but I saw that you forgot MAPP gas aka "yellow gas" MAPP gas - Wikipedia, the free encyclopedia
I have never heard of anyone using MAPP in airsoft, but I guess it is possible. I will add it later. After I get some better details on it.
I first heard about from some of the Euro guys running WE's in Finland, Holland, and a couple from Northern Russia. You really don't want to use it if the temps are over about 40-45 degrees F (sorry, don't know the C equiv for that off hand).

My very limited testing was in my KC-02 at about 40F. I got 450fps on a .2g bb (which is about the same readings at about 75F+ and propane for my rifle)
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Wow, this is great!!! I am sure that this could really help some new guys that are just getting into gas guns and such. Great thread Plazma!!

I vote for sticky.
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added MAPP, MAP//Pro, Propylene.

@timmah - I do not question your results, but I think you may be using MAP//Pro instead of actual MAPP.
As to Black gas, there is still discussion going as to whether or not it ever actually existed, or was just someone making it up to make their gun sound more durable. Could be one of the reasons there's not much info to be found about it.
Yellow gas was/is used around here (Netherlands, Belgium) region as Powergas/redgas.
It is uncommon nowadays, and people often run Red-gas/powergas instead.

I heard a rumour that red-gas/power gas/sniper gas is just pure-ish propane.
MAPP gas is highly flammable when mixed with oxygen so I hope it isn't used in it's pure form lol
I've used MAPP gas in my gas ... It's exactly like propane.
It's much easier to find than normal propane... at least where I live!

Has anyone of you tested green gas with fire? It's exacly the same as propane!

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Green gas has silicone in it and is slightly less flammable than regular propane that you buy from walmart (which is why you have to spray silicone yourself if you just buy propane gas to use)
Plasma, you may want to check the "recert date" section. If memory serves me correctly... metallic tanks are hydro test every 5 years and carbon fiber are hydro test every 3. This is because carbon fiber has a much better chance of becoming damaged than metallic tanks over the course of usage.
I know for sure carbon fiber is 5 years. Don't know about aluminum/steel. I think it is 5 also.
I know for sure carbon fiber is 5 years. Don't know about aluminum/steel. I think it is 5 also.
Not all carbon fiber. It depends on the maker. Some of them are 3 years, some are 5 years. This also dictates how long the tank may remain in use before it must be discarded (as in can no longer be hydro tested)

My Pure Energy tank is every 3 years:

And my Crossfire tank is every 5 years:

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Huh ok. I have two new ones and they are both 5 years.
My PE tank's in-service date is from 2007 so they may have done away with 3 year tanks now... But that would be a shame because according to the DOT rules, 3 year tanks are good for up to 18 years from the in service date whereas 5 year tanks are only good up to 15 years.
I will make an amend to that, my PE tank is a 5 year: manufacturer is Luxfer.

A1 fire and safety said aluminum tanks are 3 years, they do hydrotesting for my local PB shop. This is also what my PraxAir rep told me as well. I will double check next time I go by either one.
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