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What is Power?

Some airgun enthusiasts believe that the quality of an air rifle is derived from it's power level. Power can be calculated in a variety of ways.
For instance, a rifle's power is rated on velocity and muzzle energy, while a pellet's power is rated on its kinetic energy (knockdown power).

Determining velocity requires the use of a chronograph. Or you can also review the rated listings which are based on rifle manufacturer's information. generally using the lightest possible pellets. When using heavier pellets, the velocity decreases although the relative knockdown power (kinetic energy) usually increases. For this reason you should take the listed manufacturer ratings with a "grain of salt".

Airgun rifle power can be loosely be categorized into three groupings: Light, Medium and High.
High power is generally any velocity rating over 900 fps in a .177 caliber. As the caliber (size) of a pellet increases from .177 to .25 the velocity decreases. You would not expect to find your average .25 caliber air rifle shooting at 900+ fps. For this reason Muzzle Energy is also used to explain power. The higher the muzzle energy, the greater the knockdown power thus the greater the overall power of the gun.

A magnum rifle works well for general shooting and hunting. A velocity rating for a magnum air rifle can range from 800-1000+ fps. This power rating is good for hunting although that much velocity isn't really necessary for pest control and hunting.. Shooters tend to look at a rifle's velocity rating for hunting, but it is really the accuracy and kinetic energy (knockdown power) that determines the effectiveness of a hunting rifle rather than the velocity.

A rifle of standard power typically has velocity ratings ranging from 700-850 in most calibers. That will yield great results for general plinking, pest control and hunting of small game. And in fact, most spring air rifles fall into this velocity range.

The Light rating can be considered a power rating under 700 fps in .177. Generally, Light Powered rifles come in power settings of 600-700 fps and muzzle energy of less than 10 foot pounds. Do not confuse a light powered air rifle with a velocity of 650-700 fps with a match rifle though. A match rifle is designed to be extremely accurate for 10 meters. To this end accuracy is more important than power and velocities are usually in the 500-600 fps range for Match rifles. Generally speaking, in an out-of-the-box spring gun, the less power the gun has, the less recoil and motion it has.

Note that these power ratings and classifications do not hold true for pistols. Power in a spring gun is developed from a heavy duty spring under tension. The size of a pistol will limit the amount if power a spring pistol or single cock pneumatic pistol is able to develop. PCP pistols, however, can achieve quite high power ratings due to the use of high pressure compressed air.

Kinetic Energy is really the most accurate way to assess a rifle's power. Power is most important to a hunter or a long distance target shooter. Kinetic Energy is the actual knockdown power at the target, not at the muzzle. A rifle with a lot of kinetic energy does a better job for the hunter. But while the target shooter isn't really concerned with knockdown power, he is concerned with the ability of a pellet to retain it's velocity and power as long as possible. The better that a pellet retains its energy (and coincidentally knock-down power) the better the pellet's trajectory will be for the target shooter as well.

When selecting a rifle it is wise to determine its intended use. Hunters should determine the type of game and distance needed for their type of hunting purpose. Typical hunting ranges are from 20-50 yards. If your intended quarry will be small birds and ground squirrels, you might consider a rifle with 4-6 ft. lb. of power at the target. If you aren't sure how to do that, check the Our Take section on this site. It lists many airguns in all calibers and the results from shooting many different pellets. The Our Take shows the power level in fpe (ft. lbs) at the Muzzle, 10, 25 and 50 yards. It will make a very good reference for you for most air rifles.
If you are looking to take larger game or game at a greater distance, remember that you will need the same 4-6 fpe for small game kills at whatever distance you are shooting, long or short. If your intended use is target shooting and indoor shooting, accuracy is more important than power.

For those shooters interested in power we have listed our rifles based on the three categories. Just select a power level and review the guns listed. If muzzle velocity is more to your liking however, view our listing of rifles by muzzle velocity.