Length of pull (sometimes abbreviated as LOP) is the distance from the

trigger Trigger may refer to: Notable animals and people ;Mononym * Trigger (horse), owned by cowboy star Roy Rogers ;Nickname * Trigger Alpert (1916–2013), American jazz bassist * "Trigger Mike" Coppola (1900–1966), American gangster ;Surname * Bru ...

to the part of a

rifle A rifle is a long-barreled firearm designed for accurate shooting, with a barrel that has a helical pattern of grooves ( rifling) cut into the bore wall. In keeping with their focus on accuracy, rifles are typically designed to be held with ...

shotgun A shotgun (also known as a scattergun, or historically as a fowling piece) is a long gun, long-barreled firearm designed to shoot a straight-walled cartridge (firearms), cartridge known as a shotshell, which usually discharges numerous small p ...

which fits against the

shoulder The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder mak ...

of the shooter. Length of pull is an important

ergonomic Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. Four primary goals of human factors learnin ...

factor for ease of use; and optimum length of pull may vary with the size of the shooter, the thickness of

chest The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...

clothing and

body armor Body armor, also known as body armour, personal armor or armour, or a suit or coat of armor, is protective clothing designed to absorb or deflect physical attacks. Historically used to protect military personnel, today it is also used by variou ...

being worn, and whether the shooter is firing from a

standing Standing, also referred to as orthostasis, is a position in which the body is held in an ''erect'' ("orthostatic") position and supported only by the feet. Although seemingly static, the body rocks slightly back and forth from the ankle in the s ...

sitting Sitting is a basic action and resting position in which the body weight is supported primarily by the bony ischial tuberosities with the buttocks in contact with the ground or a horizontal surface such as a chair seat, instead of by the lower l ...

, or

prone position Prone position () is a body position in which the person lies flat with the chest down and the back up. In anatomical terms of location, the dorsal side is up, and the ventral side is down. The supine position is the 180° contrast. Etymolog ...

Variation

Many rifles and shotguns are manufactured with a standard length of pull assumed to fit most shooters. This is often approximately for rifles and about longer for shotguns. Shooters with short

arm In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint (shoulder joint) and the elbow joint. The distal part of the upper limb between th ...

s may find the

buttstock A gunstock or often simply stock, the back portion of which is also known as a shoulder stock, a buttstock or simply a butt, is a part of a long gun that provides structural support, to which the barrel, action, and firing mechanism are attached ...

dragging along the underside of their arm as they attempt to raise the firearm into firing position. Shooters with broad shoulders or a long

neck The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In ...

may experience face injuries from collision with the

telescopic sight A telescopic sight, commonly called a scope informally, is an optical sighting device based on a refracting telescope. It is equipped with some form of a referencing pattern – known as a ''reticle'' – mounted in a focally appropriate po ...

thumb The thumb is the first digit of the hand, next to the index finger. When a person is standing in the medical anatomical position (where the palm is facing to the front), the thumb is the outermost digit. The Medical Latin English noun for thumb ...

of the trigger hand as the firearm

recoil Recoil (often called knockback, kickback or simply kick) is the rearward thrust generated when a gun is being discharged. In technical terms, the recoil is a result of conservation of momentum, as according to Newton's third law the force requ ...

s. Modern firearms may be equipped with a

telescoping stock A gunstock or often simply stock, the back portion of which is also known as a shoulder stock, a buttstock or simply a butt, is a part of a long gun that provides structural support, to which the barrel, action, and firing mechanism are attached ...

or removable spacers to adjust the length of pull.

Gunsmith A gunsmith is a person who repairs, modifies, designs, or builds guns. The occupation differs from an armorer, who usually replaces only worn parts in standard firearms. Gunsmiths do modifications and changes to a firearm that may require a very h ...

s may adjust the length of pull of custom-built firearms or older firearms by cutting off a portion of the buttstock or adding a

recoil pad A recoil pad is a piece of rubber, foam, leather, or other soft material usually attached to the buttstock of a rifle or shotgun. Recoil pads may also be worn around the shoulder with straps, placing the soft material between the buttstock and the ...

to the buttstock. Some sources suggest a shooter's optimum length of pull will allow the butt of the firearm to exactly reach the inside of the

elbow The elbow is the region between the arm and the forearm that surrounds the elbow joint. The elbow includes prominent landmarks such as the olecranon, the cubital fossa (also called the chelidon, or the elbow pit), and the lateral and the media ...

when the hand of that arm grips the unloaded firearm with a finger on the trigger. Other sources suggest a more appropriate determination may be made using a non-firing "try-gun" resembling a firearm with an adjustable buttstock. When a properly adjusted try-gun is held in a firing position, the shooter's

nose A nose is a protuberance in vertebrates that houses the nostrils, or nares, which receive and expel air for respiration alongside the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes th ...

should be about two

finger A finger is a limb of the body and a type of digit, an organ of manipulation and sensation found in the hands of most of the Tetrapods, so also with humans and other primates. Most land vertebrates have five fingers ( Pentadactyly). Chambers ...

-widths behind the thumb of the trigger hand.

Sources

{{Firearms Firearms