The Air Rifles range from simple pellet
rifles to custom European rifles, there are hundreds of
variations of rifles, and of adjustments on the rifles
themselves to custom fit an individual shooter.
Despite this the workings of the rifles are essentially the same. An air cylinder of compressed air is attached to the gun, and a regulator. A single-stroke lever cocks the gun, and the trigger releases the pressurized air, which propels a .177 caliber pellet.
The pellet is propelled down the rifled barrel, which has ridges and grooves that spiral around the inside of the barrel that causes the pellet to spin as it leaves the barrel and travels through the air. The spin causes the pellet to follow a straighter more accurate trajectory. Since the pellet is traveling in the horizontal direction it has the velocity from the initial propulsion of the air. The other forces acting on it are the air resistance, which would only have a small effect due to the short distance traveled. There would also be drag acting on the pellet as it is in the air, but they are designed to use this force to stabilize itself during flight.
Another force acting as the air rifle is Newton’s Third Law of Motion, that for every action there is an equal and opposite reaction. The released air that propels the pellet has a force in the direction of the target (hopefully). As this occurs there is an equal and opposite reaction that is directed toward the rear of the rifle and therefore the person holding the rifle. This force is enough to propel the pellet at around 300 to 400 meters per second; when it’s equal and opposite force acts on the person holding the rifle is relatively small due to the significantly greater mass of the person when compared to the mass of the pellet.
This recoil is minimal when compared to the recoil of more common firearms. The air rifles are designed so that this equal and opposite force is the only one enacted and other movements, like vibrations, are absorbed into the system of the rifle and do not affect the shooter.