William Powell Country

William Powell’s Guide to Air Rifles


Article written by 23 August 2012


There are two main calibre choices when it comes to air rifles .22 and .177. There are pros and cons for both and everybody will have their own opinion on what is best, but we have set out below what after over 50 years selling them, we believe;

.22 (5.5mm)


Larger mass means greater stopping power up to 40 yards

Great all-round calibre for most activities, particularly vermin control. If you are wanting to shoot rabbits, rats, pigeons, the .22 is better than the .177


More expensive than .177

Slower than .177

Large “drop” in the pellet over 35 yards, therefore less accurate at a longer range.

.177 (4.5mm)


Smaller mass means increased velocity, therefore less “drop” in the pellet over 35 yards.

Tend to be lighter than .22’s therefore more easily carried by the young.

Greater effective range than .22 because of the lack of “drop” and more accuracy.


Smaller mass means less stopping power, therefore very good for target shooting but less stopping power for vermin

Have to be more accurate to ensure clean kills

Smaller range of pellets available


There are a number of power sources air rifles use to push the pellet out of the barrel. The most popular are:


A large mainspring is located to the rear of the barrel and is compressed either by cocking the barrel or by using an under lever. When the trigger is pulled, the spring is released and a piston at the end of the spring pushes the air down the cylinder and out of the barrel thus propelling the pellet. The benefits are simplicity, cost, and no need to re-fill. The downsides are a slight ‘recoil’, they are relatively noisy and not the most accurate because of the ‘recoil’ and they also have slightly heavier triggers. However, these are only relative disadvantages as compared to their many advantages, including cost, simplicity and reliability.


Disposable gas canisters are required to power a Co2 gun and these are inserted into the gun and sealed. The high pressure gas from these canisters then fills a special valve. These guns are usually bolt action and by working the bolt you do two things;

1) cock an internal hammer

2) insert a pellet into the breech.

When the trigger is pulled, the internal hammer hits a rod connected to the valve and opens it letting a small ‘burst’ of gas down through the barrel thus propelling the pellet. The benefits are cost, and lack of ‘recoil’. The downsides are the running costs to buy Co2, low power so as to get enough shots per Co2 canister, often poor quality as the majority are made cheaply in China and poor reliability because of the amount of poor quality moving parts.

Pre-charged pneumatic (PCP)

Is very similar in mechanics to Co2, however of much higher quality and usually up to the legal power limit (12 ft lbs). These use compressed breathing air from a diving cylinder or special stirrup pump and the re-usable tanks are filled by the user at a diving shop or scuba school. These guns can often have magazines containing 8-14 pellets so there is no need to reload every time you fire. The benefits are a lack of recoil, extremely accurate, can be silenced and very good quality.

The bad points are they are quite expensive to buy and filling them up can be hard work when using a stirrup pump. (I.e. if you don’t go to a dive shop or similar.)


Most modern air guns are used in conjunction with a telescopic sight mounted on top of the gun. These vary in price from £30 to several hundred £s but essentially all do the same thing; magnify the target and give you an aiming point (crosshairs). Generally the more money you spend, the better the lenses will be and therefore the clearer the view. Scopes vary in magnification. A typical air rifle scope will be 4×32 i.e. 4x magnification and a 32mm front (objective) lens. Other popular specifications are 3-9×40, 3-9×50 or 4-12×50. The cost is usually between £30 and £1000, but for around £40 to £150 you get a good, reliable and accurate scope.


The power of an air rifle is measured in ft lbs. In the UK all air rifles must be below 12 ft lbs (unless you have a Firearms Certificate). You must be 18 years of age to buy an air rifle or use one unsupervised.

An air rifle can be bought for someone between the ages of 14-17 as long as they use it on private property while under supervision from someone aged over 21.



Daniel Todd (William Powell Gun Room)

Dan previously formed part of the William Powell team, a gun expert based in the Gun Room. Read more.

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