Pellet being shot from a CO2 Air Rifle – Surplus Store

Are you looking to buy a new air rifle, but haven’t quite decided what kind you are looking to buy? We have decided to take a look at CO2 air rifles, and some of the facts surrounding them to try and aid you in your decision making:

CO2 guns do not lose velocity when shot

When using a CO2 powered rifle, the first few shots will be faster, due to a small build-up of CO2 liquid in the firing valve or barrel. This will then expand, which increases the density of the gas charge. Once this has been dispersed, you will gain a long string of shots at a consistent velocity, for the duration of the life of the charge. At the end of the liquid CO2, the pressure will begin to drop rapidly, which will cause velocity to drop. This can be corrected by recharging or inserting a new CO2 capsule into the rifle.

One thing that will cause velocity to drop is rapid firing of a CO2 rifle, which causes the gun to cool down. If firing is slowed down, the velocity will start to increase again.

Maintenance is key

Of course, as with any air rifle, it is important to keep good care of it, and maintain it correctly. A CO2 rifle depends on its seals to hold in the gas, and therefore keep the pressure up. Most of the seals are O-rings, which require a small layer of oil to work effectively. CO2 rifles prefer silicone oil for this, so this should be used during the care of your rifle.

CO2 gun means CO2 gas

A CO2 powered rifle is called that for a reason – it requires CO2 to work efficiently, and will not operate well with other gases. In order to operate correctly, a CO2 rifle will need a constant pressure level of around 900 psi, which can only be offered by CO2 at room temperature. If you were to pressurise a CO2 gun to 900 psi using regular air, the first few shots would be quite powerful, but velocity would soon drop off quickly, along with pressure. This is due to the fact that air is much thinner than CO2, and therefore flows through the valve faster.

Pressure and velocity depends on temperature

This is where a CO2 rifle can be slightly temperamental, as the temperature of where you are shooting can have varying effects on your shot. For example, if the weather is warm, the gun will shoot faster. Cold weather is generally a no go for CO2 shooting, as CO2 lacks the required pressure to propel pellets at lower temperatures.

Barrel length determines velocity

This is true to a great degree, due to the way CO2 works. It is very similar to black powder, in the regards that they need a certain amount of time in order to reach maximum working efficiency. Therefore, a longer barrel will allow more time for the CO2 gas to expand and create more pressure to push the pellet out with.

These are just a few things that we have taken a look at surrounding the CO2 powered air rifle. If this sounds like the right kind of rifle for you, head on over to our website and take a look at our extensive range of CO2 powered air rifles.



Photo courtesy of Hohum, under Creative Commons