Is green gas propane or is it like propane?
So it's really propane? How can you be sure?
So, why should I fill my gun with propane instead of green gas?
Isn't it flammable?
How come green gas smells different than fuel propane?
Some brands of green gas are lubricated. Is propane?
What about my slide breaking, or seals being damaged?
Will my gun perform the same on green gas and propane?
Will propane damage my gun?
Are propane tanks safe to carry in the field?
How come we've been using propane, and nobody knew?
Can I see your test results?
Is green gas propane or is it like propane?
Green gas is not like propane. It is propane. Green gas is not R22, or Co2, or "CH2FCF3CH3" (as seen on some bottles). It is merely run-of-the-mill propane, with a different scent added.
So it's really propane? How can you be sure?
Samples were sent to the Analest Laboratory at the University of Toronto where 3 brands of green gas (Jet, Green Power, Shooting Air) were analyzed with a gas chromatograph/mass spectrometer, an industry standard for organic gas assaying. All 3 gases were shown to be propane. Additionally 3 more brands have shown to be similarly flammable and exert the same pressure. Test results, discussion and conclusions can be found in the Lab Data section, please read the Laboratory Analysis of Green Gas for more in-depth information.
So, why should I fill my gun with propane instead of green gas?
If you use green gas, you're already using propane. Domestic propane is cheaper, comes in a safe container, and is available at any local hardware store. Airsoft bottled propane (green gas) has to be imported (which can take a long time).
Isn't it flammable?
Green gas has always been flammable. Now that we know it's propane, nothing has changed. You should never ignite propane/green gas, or release it near an open flame. However, propane is fairly safe for normal use - we already use butane (another flammable gas) in many consumer products, such as shaving cream and hairspray, and propane is used as an industrial refridgerant (it's also known as HC290).
How come green gas smells different than fuel propane?
Fuel propane is scented with mercaptan odourants for leak detection. By itself, propane has very little smell. Different bottlers of fuel propane use different odourants and so do green gas bottlers hence the different smells. Green gas and fuel propane are primarily propane so they all perform similarly in the end.
Some brands of green gas are lubricated. Is propane?
Propane is not lubricated. However, the design of the AI Gungas propane adaptor makes it easy to mix silicone oil into your magazine fill charge, and includes an instructional video detailing exactly how to do it. Airsoft Innovations also carries ultra-lightweight silicone oil ideal for GBB maintenance.
What about my slide breaking, or seals being damaged?
Green gas is propane, we've been using it all the time, there is no difference. Add a few drops of silicone oil, as shown in the AI Propane Adaptor instruction manual, and your gun will be just as well off as with "green gas". You shouldn't use propane/green gas in any gun that is not designed for higher pressures (e.g. un-upgraded Western Arms GBB's). Some GBBs are designed expressly for the use of HFC134a (a lower pressure gas). Propane is not a good substitute for HFC134a in GBBs designed for HFC134a.
Will my gun perform the same on green gas and propane?
I have some chrony results comparing propane from a Coleman stove tank and a brand of gas called "Shooting Air". Tests were conducted with a SVI 3.9" with metal slide shooting 0.25g bbs. Shots were done with a completely filled mag allowed to warm up to room temperature for 30min. Shots were fired every 5 seconds to reduce cooldown.
| Propane (fps) | 289 | 285 | 283 | 275 | 273 |
| Shooting Air (fps) | 281 | 282 | 281 | 277 | 280 |
Will propane damage my gun?
GBBs modified to handle green gas (we really have to stop saying green gas) are already propane ready. Certain GBBs in stock form (WA, TM to name a few) are not propane ready. The higher pressure of propane can overstress a stock plastic slide and cause it crack or completely break. Still, many users fire them on propane as they consider the performace/durability tradeoff acceptable.
Are propane tanks safe to carry in the field?
Yes. Most disposable propane fuel containers feature overpressure relief valves which allow propane to leak out before a can is over-pressurized and explodes. They are also of heavy steel construction which withstands very high pressure. Conversely, green gas bottles are thin walled aluminum without overpressure protection. In a few cases, these containers have exploded with frightening result. In one case, shrapnel from an exploded green gas can perforated a vehicle roof.
How come we've been using propane, and nobody knew?
The suspicion has floated around for a few years, but until now, no one got around to actually testing the stuff in a lab. Green gas has always been mislabelled, with fake chemical formulas and incorrect pressure specifications – nobody questioned them.
Can I see your test results?
Absolutely. I've compiled all my testing data, results and conclusions in the Lab Data section, please read the Laboratory Analysis of Green Gas for more in-depth information.