Everything you need to know about airsoft gases or propellants
CO2 (Carbon Dioxide) is a non flammable gas, typically in a disposable metallic cartridge/cylinder filled with 12 grams of CO2 and filled to a pressure of approximately 800 psi (temperature dependent). They are convenient and readily available all over United States and can be found at almost any sporting goods/big box store. We find their surplus of pressure typically allows it to work at lower ambient temperatures then Green Gas even though CO2 is typically affected by cold weather, much like any gas that is stored in a liquid form and expanded to a gas during use. We usually recommend CO2 to anyone who lives in an area where they will be using their Airsoft Gun outside where they will be experiencing cold temps or in an area where you can't easily go to your local Airsoft store to purchase Green Gas. CO2 cartridges, typically do not have any sort of lubricant mixed into the gas to help keep your Airsoft Gun lubricated and keeps your seals from drying out.
Green gas can be referred to as HFC22 depending on where you are from. Overseas there is lower pressure gas such as HFC134a and some higher ones but for now we're going to talk about what is commonly available in the US, Green Gas. Green gas is the fuel or propellant used for gas blowback airsoft guns. It is a pressurized flammable gas that comes in a can. You would transfer the contents of the can into the magazine of your gas airsoft gun. Typically a 3 to 5 second charge is enough to fire the airsoft gun to completion. The nice thing about green gas is that you can always keep your gun topped off with gas at any time. When filling a Green Gas magazine with Green Gas, you have to hold the airsoft gun magazine and gas can upside down (gas can on top, fill needle facing down towards the ground.) This is necessary to get the liquid gas inside the can into your magazine. If you do not fill your magazine this way, you will only get a couple of shots off per charge as you will be relying on the expanded gas at a pressure of around 115psi. By filling the magazine up with liquid gas, you can get many more shots off as the gas can expand from a liquid to a gas. While you can't over fill a Green Gas magazine by filling it for longer then 3-5 seconds (you're just equalizing the pressure between the gas can and the magazine and transferring liquid into the magazine) you could be wasting your Green Gas, especially if you have a non leak free fill valve. These valves typically spray fuel out while transferring gas to your magazine. Some guns have a leak free style fill valve and these will usually just make a hissing noise and not have as much or any green gas spray out while filling. Either valve is fine, but this is the reason we recommend not filling beyond 5 seconds. Green Gas has a lubricant mixed into the gas to help keep your seals lubricated and operating smoothly. Green gas has a reasonable operating range for temperature but it is not recommended on cold days below 60 degrees F or you could expect sluggish performance. The chemical makeup of green gas is similar to that of propane so you can use them interchangeably if inclined. The main difference between green gas and propane though is propane being used in many things can be found in different pressure ranges. Also there is an added smell to warn humans of a dangerous gas leak. Propane lacks the silicone additive found in green gas so running propane in your airsoft gun could potentially dry out the seals sooner and you should add silicone oil yourself to supplement. Silicone oil is sufficient for airsoft guns so do not use something like WD-40 or gun cleaning compounds as those items contain petroleum which would be caustic on these o-rings.
Word of caution if you are using green gas: Do not puncture the can and do not inhale its contents. Use only in a well ventilated area. Green gas is toxic and flammable. Due to its pressurized nature, do not put a can out in direct sunlight on a hot day or leave it inside your vehicle during the summer months. The can may build pressure and eventually explode.
Propane can be used with a propane adapter for a convenient, cost effective solution to Green Gas. While straight propane is not typically recommended for long term use in your airsoft pistol, it is still a viable, affordable solution for those that do not have a store where they can purchase green gas canisters locally. A propane adapter, attaches the very common green and blue (16oz and 14oz, respectively) propane tanks found at any sporting goods or home improvement center. With propane you MUST add your own silicone oil to keep your airsoft gun operating longer. Failure to add additional lubrication will result in seal failure.
Question & Answers
Q: Why can't I purchase a single can of green gas on your website?
A: Due to the flammable nature of Green Gas it must be shipped as a Hazardous Materials (HAZMAT) shipment and isn't cost effective to purchase a 10 to 15 dollar can of gas + shipping + a HAZMAT fee of approximately $30 dollars. For this reason it only makes sense to order a full case or two of Green Gas (36 cans per case) to help spread the HAZMAT fee over each can. We recommend purchasing Green Gas at our retail location or your local airsoft store. If you do not have a local source for Green Gas, please purchase a Propane Adapter, CO2 gun or compatible CO2 magazine if your airsoft gun can take this type of magazine.
Q: Can green gas guns use CO2?
A: CO2 is higher pressure than green gas. If you manage to somehow adapt CO2 to be fed into a green gas gun, it will not last very long due to the high pressure. CO2 guns are built stronger to handle CO2. However some makers have airsoft guns that are dual compatible which means it was built for CO2 already but have the option of a green gas magazine. Whatever you do, do not inject CO2 into a magazine or grenade designed for Green Gas, the magazine or grenade can explode and seriously injury or kill you. But it is okay to use a magazine made for CO2, in a gun that was designed to accept and operate on Green Gas and CO2.
Q: How do I use propane?
A: Propane is an alternative to green gas (the chemical makeup is pretty much the same). There are adapters available from us that can add a fill valve to the commonly found camping propane tanks that you can get from many places. Make sure to fill your magazine upside down (Propane tank on top, fill valve/needle facing toward the ground) to get as much liquid propane into the magazine as you can. You should also apply a drop or two of silicone oil between the propane adapter and propane canister every few magazines to help inject oil into your airsoft gun magazine.
Q: How do I lubricate my gas gun?
A: Apply silicone oil to the slide rails and any part that moves that makes contact with each other. You will also want to lubricate the O-rings and valves inside the magazine. To lubricate, simply apply a dot of silicone on the fill valve. Then fill the magazine for but a second pressurize it. The pressure will help disperse the oils to any leaky areas or to any seals it comes into contact with.
