Can You Leave a CO2 Cartridge in an Airsoft Gun?

Airsoft guns are a fun hobby for people of all ages to enjoy, and they’re much safer than traditional firearms, while still maintaining the realism that most enthusiasts crave. However, this realism comes with a hefty price tag, so maintenance and proper handling are critical. For example, is it okay to leave your CO2 cartridge in your airsoft gun when you’re done shooting?

You can leave a CO2 cartridge in an airsoft gun, but not for long periods. The gas in the cartridge keeps a small amount of pressure on the internal seals, which can be beneficial for the gun. Gas leaks out over time, leaving the weapon inert, so cartridges should be removed when storing the weapon.

This article will discuss the pros and cons of leaving the cartridge in the gun versus taking it out. It will also go into the internal workings of an airsoft gun.

How CO2-Powered Airsoft Guns Work

To understand why you should or shouldn’t take the CO2 cartridge out, you need to know how these guns work so that you can make an informed decision.

There are two primary types of airsoft guns:

  • Spring-powered
  • Pneumatic (gas-powered)

This article will focus on CO2-powered pneumatic guns.

Pneumatic airsoft guns use pressurized gas inside of a cartridge to expel the BBs from the barrel. There is no need for any chemical reaction or “explosion” like there is in a traditional firearm. These cartridges should be placed in the magazine of the weapon.

Once you squeeze the trigger, gas goes to the gun’s barrel and propels a BB through the air. Gas is then sent backward towards the cartridge to seal and close the valve. 

The last step is crucial to maintaining pressure inside the cartridge. If this backward pressure didn’t happen, the cartridge would lose all of its gas on the first trigger pull. For a visual demonstration of this process, check out this video:


As you continue shooting, you are using small amounts of gas from the cartridge. Eventually, you will run out of gas, and you will need to replace the current cartridge with a new one. A fresh cartridge can last you anywhere from 20-200 shots depending on the size of the cartridge, temperature, and the type of gun you’re using.

What Happens to a CO2 Cartridge When Left in an Airsoft Gun

Constantly replacing cartridges can be a pain and can become expensive. If you’ve only used half of the gas, it would be frustrating to have to get rid of it. So what would happen if you left the cartridge in the gun? 

As long as the seals on the weapon and the cartridge are in working order, no damage will be done by the leaking gas.

Here is a guide on how to stop your gun from leaking CO2.

In fact, according to many airsoft technicians, the internal pressures created by having the cartridge installed will increase the life of the seals. 

However, if these seals are damaged or not properly secured, the cartridge will slowly lose gas over time. Losing gas can be a nuisance because you will have to replace the cartridge, but it can also continue to damage the gun leading to expensive maintenance.

When To Leave a CO2 Cartridge Inside an Airsoft Gun

If you’re at an airsoft park and you’re taking a break between games, there will be no issues with you leaving the cartridge in the magazine. 

Any time you’re taking only short breaks between firing the gun, you can leave the cartridge inserted. Doing so will save you time and maximize the uses you get out of each cartridge. 

If you plan to store the gun for a long period, then you’ll want to remove the cartridge.

There are exceptions to that as well, however. 

For example, some people use airsoft guns for pest control around their homes. This would mean they would only shoot a couple of shots at once and may have to use it at short notice. For these users, leaving the cartridge in the magazine is a necessity, even though they may not use the gun for long periods.

In this case, you need to be sure that the seals of your gun are in working order before leaving the cartridge in for long periods. Before installing a new cartridge, you will need to lubricate all the internal parts of the chamber. You can use the Crosman Nitro Lubricating Oil from to do just that. It’s relatively inexpensive and simple to use. 

When You Should Take a CO2 Cartridge Out

When you take the cartridge out, you lose all the backward pressure on the cartridge, so you instantly lose all the air pressure. This loss of pressure leaves the cartridge unusable.

When storing your airsoft gun for an extended period, it would be wise to remove the cartridge. No matter the quality of your seals, you run the risk of those seals drying up and permanently damaging your gun. Cartridges are relatively inexpensive, so it is better to err on the side of caution.

Another reason to remove the cartridge from your airsoft gun is if you have small children that can gain access to the weapon. Just like with traditional firearms, it is your responsibility as the gun owner to be sure that no one is exposed to the risk of operating the weapon without the proper knowledge. By removing the cartridge, you leave the gun inert and unable to be fired.

Final Thoughts

You can leave your CO2 cartridge inside your airsoft gun, but the length of time for which you do so will determine your risk of damage. If you’re only leaving it for a few hours or days, you should be okay. If you’re leaving it for weeks or months at a time, you should remove the cartridge before storing it.

Whether you’re installing a fresh cartridge in the middle of your day at the park or preparing the gun for long-term storage, it’s always best to lubricate the cartridge before installation so that the seals don’t dry out.