Green Gas vs CO2: Which Should You Pick?

Kai Banks

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Green gas vs co2 featured image

If you’re looking to buy an airsoft pistol, you might’ve pondered the green gas vs CO2 question.

Which is better? Which is cheaper? Which should I get if I’m a beginner? What even is the difference between green gas and CO2?

Don’t worry, you’ve made it to the right place. In this article, we’ll explain the difference between both options, how they work, and which one is best for you.

The Quick Rundown: Green Gas vs CO2

Green gas and CO2 guns are pretty similar. They both work with pressurized gas tanks that send BBs flying by releasing a small part of said gas. The guns that work with either option are pretty similar in price, just like the replacement green gas or CO2 canisters.

So what’s the difference?

The main technical difference is in pressure – CO2 cartridges are MUCH more pressurized than your average green gas tank. This in turn can output more power, so your BBs will fly faster. But it also damages your gun’s internals more quickly. A green gas airsoft pistol will generally last longer than a compressed air alternative.

The substance itself also plays a part. Green gas guns lose a lot of power and accuracy when you fire more shots in quick succession, or when the gas supply gets low. CO2 guns maintain consistent power until the canister runs out.

But in the end, it’s a matter of preference really. Both green gas and carbon dioxide are good choices. You choose green gas for better gun durability and the guarantee that you can take it to any field, regardless of the FPS limit. You pick CO2 for more power and more consistent power output.

If you’re curious about a deep dive into each of these firing mechanisms, read on.

What is Green Gas?

Green gas might make you think about “greenhouse gases,” but it’s not methane. Green gas is just propane, with some silicone oil added to it. There are other variants, but for the most part, that’s what you’ll find in green gas cans.

Gree gas airsoft pistols have an internal tank, that you fill up with green gas canisters, much like you would a lighter.

This might worry you – is green gas safe?

Green gas airsoft guns are mostly safe, even if the propane and silicone oil sound dangerous. The compressed gas is not toxic unless inhaled in high quantities, and it’s not more dangerous or flammable than your average hairspray or deodorant.

Still, you shouldn’t take it anywhere near an open fire. Just exercise common sense and you’ll be fine.

Green gas pros and cons


Very realistic weapon operation

Relatively safer than CO2

Doesn’t damage gun parts as much as CO2


Not as powerful as CO2

Still dangerous if mishandled

Magazine gets cold and you lose power after firing rounds in quick succession

Not ideal for full-auto or target practice

Green gas guns have a unique oomph when you shoot them. They’re safer than CO2, keep your gun in pristine condition, and green gas pistols usually have a very realistic operation. Some rifle models are even used in the training of military personnel because they’re so accurate to disassemble.

On the other hand, green gas magazines will get really cold when you fire more shots in quick succession. This makes green gas guns lose power in intense firing scenarios. Additionally, the FPS starts dropping considerably as the green gas tank gets on low supply. So it’s not the perfect pick for full auto airsoft guns or intense target practice.

Lastly, a green gas gun usually has less FPS than its CO2 cousin. But not by a lot. And for a lot of players, this is actually a plus. Sure, the 400 FPS you’d get in a CO2 airsoft gun feels good. But you can take a 300 FPS pistol to any field without worrying about power caps. And this is especially important if you play indoors.

When to pick green gas

If you want realistic weapon operation, especially when disassembling your pistol, pick a green gas option.

If you want a durable pistol, pick green gas counterparts. The lower pressure in a green gas magazine doesn’t damage the gun’s internals as much as CO2 canisters do.

And lastly, if you want a gun you’ll be able to take to any airsoft game, go with green gas. The lower FPS on green gas options means you won’t be turned away for packing too much power.

In our opinion, the best green gas gun to pick is KWA’s M9 replica:

Accurate Design
KWA M9 PTP Full Metal
9.4/10Our Score
  • Accurate 1:1 scale design
  • Double-Action / Single-Action trigger design
  • Realistic takedown
  • Realistic blowback action
  • Shoots up to 350 FPS

What is CO2?

As you might’ve inferred, CO2 guns work with gas canisters that are filled with compressed carbon dioxide – simple air. The CO2 canisters you put in your airsoft guns are under much higher pressure, so you get more powerful guns.

But that’s not just a good thing. For one, airsoft fields limit the amount of power your weapons can shoot with. Unlike green gas powered guns, a 400 FPS pistol might not be allowed in indoor games. Additionally, more pressure means more damage to your gun’s internal parts.

So are CO2 guns worth it? Let’s talk pros and cons.

CO2 pros and cons


More powerful than green gas

Consistent firing until the tank runs out

Good for full auto and target practice


Higher pressure damages the internal components of your airsoft gun

Not all fields will let you use powerful pistols in games

CO2 is pretty straightforward. It’s more powerful than green gas, and it fires at a consistent FPS until the tank runs out. This makes it really good for full-auto or semi-auto guns, as well as target practice. 

On the other hand, the higher pressure of CO2 canisters will damage your airsoft gun in time. Moreover, not all fields might let you use 400 FPS pistols, especially if you’re playing indoors.

So when is it worth it to buy a CO2 gun?

When to pick CO2

If you want more power in your gun, the choice is simple. CO2 airsoft guns will always pack more punch than green gas alternatives.

If you want a gun to use in target practice, and if you like full-auto or semi-auto pistols, CO2 is your best bet in both cases.

If you don’t know what CO2 pistol to get, we recommend the Umarex Glock 17:

Best Glock
Umarex Glock 17 GBB CO2
9.3/10Our Score
  • Heavy duty injection molded polymer frame w/ aluminum alloy
  • Fully licensed by GLOCK
  • Traditional GLOCK sights and trigger safety
  • GLOCK Gen.4 rough texture technology 
  • Uses KWC CO2 GLOCK magazines 
  • Realistic gas blowback 

Conclusion: Green Gas vs CO2

Whether you pick green gas vs CO2 depends a lot on what you want. 

If you’re looking for a gun to take on the field and use for years, the choice is simple: get a green gas pistol.

If you’re looking for a target practice gun that packs as much power as possible, get a CO2-powered pistol.

In my opinion, a green gas pistol is the smartest pick if you have neither. It’s just more versatile. You can use it to target practice, you can take it to an airsoft game, and it’ll last you a long time.

But they both have their pros and cons. So when you build up your arsenal, consider investing in a CO2 gun as well.

And if you liked this guide, don’t forget to read our other articles:

Written By

Kai Banks

is very passionate about two things: gaming and the outdoors. Airsoft is the best of both worlds, and that's why you'll catch us talking non-stop about everything you see on this blog.