Newton’s law about every action having an equal and opposite reaction becomes obvious, and sometimes painful, when shooting any type of firearm.
Firearm recoil or kickback is affected by the energy of the particular cartridge you are shooting, the shape of the stock, the weight of the firearm, the way the gun is held, and the body position of the shooter.
It is readily understood that the more powerful the cartridge the more kickback there will be, even when using a gun of the same weight and style. Modern rifles usually come with a recoil pad on the butt-stock to soften the blow.
As with most other components, you get what you pay for as far as recoil-pads are concerned. Cheap ones are just window dressing and more expensive ones look good and effectively reduce the impact of recoil.
Modern rifles usually come with a straight-line stock, which causes the kick to come straight back, which is easier to manage than stocks with an excessive drop at the butt, which cause the barrel to jump and drive the top of the butt harder into your shoulder.
There are right ways and wrong ways to hold a firearm while shooting, and these differences affect both accuracy and recoil.
Generally speaking, a rifle should be held firmly rather than loosely. A rifle loosely held has a chance to build up momentum before it contacts your shoulder and this makes the recoil more severe. The rifle should be mounted firmly against your shoulder in the hollow, which is two to three inches in from the outer edge of the shoulder. Your forward hand should grip the fore-end of the stock, your rear hand should hold the shaped pistol grip, and your cheek should be firmly against the top of the stock or cheek-piece, if present.
The kick will be less severe if your body can move with the rifle instead of standing still against it. As a result, shooting prone or while sitting at a bench usually results in a more severe kick, while the standing position, in which your body is free to move, often results in less recoil, provided the rifle is held firmly.
Strangely, hunters generally do not notice recoil at all when shooting at game in the field.
It is not uncommon for people to become recoil-shy and develop a flinch caused by anticipation of the shoulder smack when the gun goes off.
When this happens, the head is moved from the sights and the eyes are often closed for an instant. The shooter will not realize this is happening. This leads to movement of the gun and usually the target is missed entirely or the shots are all over the target with no consistency, which can lead to the wounding and escape of an animal, and a very sad experience for the hunter.
A lot of practice with a much lighter gun – a .22, for example – is the only way to remove a flinch from your shooting routine.