Air rifles aren’t just for plinking anymore: A hunter’s guide to the latest options

AIR POWER

Instead of burning powder to create sufficient gas to propel a bullet down the barrel, as is the case with rimfire and centrefire rifles, air rifles use compressed gas or air to launch a projectile. There are essentially five different power plants for air rifles.

SPRING PISTON: This design has been around for eons. When the trigger is pulled, a powerful compressed spring drives a piston forward, quickly compressing air to high pressure and driving the pellet down the barrel. Cocking actions to accomplish this task vary, including a break barrel, side lever or to an under lever. If you want to mount a scope on a spring-piston model, note that it must be designed for a spring gun, which recoils forward rather than rearward.

GAS PISTON: Somewhat akin to spring-piston rifles, these models are often referred to as gas-ram rifles. That’s because they use gas instead of a spring as the power source. The cocking process involves a piston compressing a cylinder filled with gas, so that when the trigger is squeezed, the gas expands and pushes the piston forward. That in turn compresses the air that drives the pellet down the barrel.

PUMP & SINGLE PNEUMATIC: Both of these models feature a reservoir that is filled by pumping it up. The pump is usually built right into the gun. With the pump design, you can increase the power level by charging the reservoir with more pumps. Most often, though, only one pump is needed to ensure a consistent level of power and accuracy. As for the single pneumatic model, only one pump is ever required to charge the reservoir. With both models, the reservoir opens when the trigger is squeezed, releasing the pressurized air to drive the pellet down the barrel.

PRECHARGED PNEUMATIC (PCP): These rifles use a reservoir of compressed air, which can vary in size and the amount of pressure involved, depending on the model. Here we’re talking about pressures of 1,500 to 4,500 psi. Almost all of the big-bore air rifles use this type of power plant, as it takes a lot of pressure to drive their large, heavy projectiles down the barrel. The reservoirs are charged using a high-pressure hand pump or the likes of specialized air compressors or air-pressure filled tanks, such as scuba tanks. When you pull the trigger, the pressurized air releases and drives the pellet or slug down the barrel. Depending on the calibre and design, PCP rifles allow for a varying number of shots—up to 75, in some cases—without needing to be recharged.

CARBON DIOXIDE (C0₂): Mechanically, C0₂ rifles work much the same as most PCP models. The primary difference is they use liquid C0₂ stored in disposable or refillable cartridges, rather than pressurized air reservoirs. The cartridges typically come in either 12-gram or 88-gram sizes. When the rifle is fired, a portion of the liquid C0₂ is instantly converted into gas, which drives the pellet down the barrel. As with the PCP power plant, this system offers multi-shot options, as well as a semi-auto function. These rifles are temperature sensitive, however, and don’t perform as well in the cold.