A commonly asked question by both new players and more experienced ones alike is often which power source is best for airsoft. Or at minimum which is better for a given weapon type. This article aims to answer which is better for airsoft , green gas vs. CO2!

Today we are going to concentrate on two of the most common gas options used in airsoft and how they relate to certain uses, regions, systems, and climates.

This topic can be a very hotly discussed one with passionate fans in both camps but in reality it really depends on what YOU need it to do.

So lets get started with Green gas vs CO2


green gas vs. CO2

Method of charging

Firstly , aside from both being a propellant gas used in airsoft they are very very different in terms of properties and practical use. So which is the better gas for airsoft when it comes to CO2 Vs Green gas ?

The first point we will look at in regards to green gas Vs CO2 is the method of getting that gas into your airsoft gun. 

With Green gas this is generally very easy as it comes in a large can that you basically inject directly into your gas magazines or in some cases bolt.

CO2 on the other hand is usually delivered into the system by way or a special magazine that has a space in it to accept 12gram bulbs which are pierced once installed. Some systems can take injected CO2 which uses an adapter that holds and pierces the bulb to inject it into the magazine.

The main thing to consider on that point is one of convenience. Green gas can easily be topped up whenever the user likes , such as between games when you know you have fired half a magazine for example. CO2 on the other hand cannot be topped up and once the bulb is pierced it cannot be removed until empty (or risk freezing the magazine and your hand as it releases all it’s gas).


Operating Pressures

The next point i’m going to address is operating pressure. CO2 is usually higher pressure at a given temperature than green gas which is essentially Propane gas. This has a couple of important effects for us . Firstly CO2 operated airsoft guns will usually have a higher muzzle energy than green gas although this is not always the case! Secondly CO2 can usually handle working at lower temperatures than Green gas.

Some brands such as KJW do build in restrictors to the CO2 magazines of their pistols so that you see very little increase in muzzle energy when changing from a green gas magazine to a CO2 one in the same pistol.

Usually gas guns do cycle a little quicker and sometimes with more felt recoil on CO2 than they would on green gas, especially in colder climates.

Also the power drop off with CO2 over the course of the magazine is usually more gradual , especially in rapid fire !

Storage and Maintenance

The third thing to consider when deciding between green gas and CO2 is storage. 

Green gas magazines like to be stored “wet” that means you should leave a small amount of gas in the magazines at all times but especially when storing them. This is to ensure the orings do not dry out and shrink would will cause the magazines to leak the next time you fill them up.

CO2 magazines should be stored “dry” which means they should be stored without the CO2 bulb in them as CO2 will perish and compromise rubber orings over time.

It is worth noting that neither magazine should ever be emptied by pressing the gas relief valve as this can damage the outlet valve!



The next point is availability, some models are only available with one or other of these power sources available. Where this is the case the product is usually optimised for that power source and therefore should be used only with that power source for best results.

Brands such as KJW, WE, VFC and GHK usually offer both CO2 and green gas magazines for their most popular systems , however brands such as KWC and RWA often only offer some products as CO2 powered.

Some brands , especially the Japanese brands such as Tokyo Marui and KSC are not designed to take higher pressure gas due to Japanese law and therefore you should avoid using CO2 in those brands !



Another big factor when considering CO2 Vs Green gas is cost . CO2 compatible guns are usually similarly priced to the green gas counterparts . However the magazines often are a little more expensive. Generally you can expect to pay 5-7 USD more per pistol magazine over green gas version and 10-15 USD more per rifle magazine . 

Also the cost of running CO2 bulbs is generally quite a bit higher than if you were running green gas. However this depends on how much both green gas and CO2 costs you locally as some regions will find one is far cheaper than the other depending upon the local market.

To summarise

All this being said there are obviously pros and cons to each propellant gas but it really does depend on what you want . Below I will add some key questions you should ask yourself when considering between CO2 and Green gas 

Firstly does the model you are looking at buying come with both options or only one ? 

Secondly do you have a local energy limit which would effect your ability to use CO2 ?

Is the extra expense of CO2 magazines worth it to you ?

Is the extra expense of CO2 bulbs worth it to you ?

Would you prefer the convenience of being able to “top up” the gas between games etc ?

What is the general climate in your region or where you play ?

Finally , can you regiment yourself to ensure you do not leave CO2 bulbs in the magazines while storing them ?

With these questions in mind you should be able to decide whether to do for CO2 or green gas for your gas guns. Personally I prefer the freedom of using green gas but I do also have some CO2 models for extremely cold weather use , however this is just my choice!



  • Good cold weather performance
  • More felt recoil
  • Less cooldown/ more consistent power curve over the magazines


  • Inconvenient once pierced bulbs
  • Somewhat corrosive to rubber
  • More expensive overall


Green Gas


  • Cheap and widely available
  • Easy to top up
  • Easy to maintain in magazines


  • Cools down faster 
  • Less muzzle energy and recoil
  • Large cans to carry around 

Whichever you choose to go for , you can find a wide variety of products on our web store at