
A light machine gun (LMG) is a light-weight
machine gun designed to be operated by a single
infantry
Infantry, or infantryman are a type of soldier who specialize in ground combat, typically fighting dismounted. Historically the term was used to describe foot soldiers, i.e. those who march and fight on foot. In modern usage, the term broadl ...
man, with or without an assistant, as an
infantry support weapon. LMGs firing
cartridges of the same
caliber
In guns, particularly firearms, but not #As a measurement of length, artillery, where a different definition may apply, caliber (or calibre; sometimes abbreviated as "cal") is the specified nominal internal diameter of the gun barrel Gauge ( ...
as the other
riflemen of the same
combat unit are often referred to as
squad automatic weapons.
Characteristics
While early light machine guns fired
full-powered rifle cartridges, modern light machine guns often fire smaller-caliber
rifle cartridge
A rifle cartridge is a firearm cartridge (firearms), cartridge primarily designed and intended for use in a rifle/carbine, or machine gun.
Types Full-powered
A full-powered cartridge is a rifle cartridge used interchangeably between servic ...
s than
medium machine gun
A medium machine gun (MMG), in modern terms, usually refers to a belt-fed machine gun firing a full-powered rifle cartridge, and is considered "medium" in weight (). Medium machine guns are light enough to be infantry-portable (as opposed to ...
s – generally the same
intermediate cartridge
An intermediate cartridge is a rifle/ carbine cartridge that has significantly greater power than a pistol cartridge but still has a reduced muzzle energy compared to fully powered cartridges (such as the .303 British, 7.62×54mmR, 7.65×53 ...
fired by a service's standard
assault rifle
An assault rifle is a select fire rifle that uses an intermediate cartridge, intermediate-rifle cartridge and a Magazine (firearms), detachable magazine.C. Taylor, ''The Fighting Rifle: A Complete Study of the Rifle in Combat'', F.A. Moyer '' ...
– and are usually lighter and more compact. Some LMGs, such as the Russian
RPK, are modifications of existing designs and designed to share the same ammunition. Adaptations to the original rifle generally include a larger magazine, a heavier barrel to resist overheating, a more robust mechanism to support sustained fire and a bipod.
A light machine gun is also defined by its usage as well as its specifications: some machine guns – notably
general-purpose machine gun
A general-purpose machine gun (GPMG) is an air-cooled, usually belt-fed machine gun that can be adapted flexibly to various tactical roles for light and medium machine guns. A GPMG typically features a quick-change barrel design calibered fo ...
s – may be deployed either as a light machine gun or a medium machine gun. Deployed on a tripod and used for sustained fire, it is a medium machine gun; if deployed with a
bipod
A bipod is a V-shaped portable attachment that helps support and steady a device, usually a weapon such as a long gun or a mortar. The term comes from the Latin prefix and Greek root , meaning "two" and "foot" respectively.
Bipods are design ...
with the operator in a prone position and firing short bursts, it is a light machine gun.
Light machine guns are also designed to be fired from the hip or on the move as a form of
suppressive fire
In military science, suppressive fire is "fire that degrades the performance of an enemy force below the level needed to fulfill its mission". When used to protect exposed friendly troops advancing on the battlefield, it is commonly called cover ...
intended to
pin down the enemy.
Marching fire is a specific tactic that relies on this capability.
Lighter modern LMGs have enabled them to be issued down at the
fireteam
A fireteam or fire team is a small modern warfare, modern military sub-subunit, subordinated element of infantry designed to optimize "Non-commissioned officer, NCO initiative", "combined arms", "bounding overwatch" and "fire and movement" mi ...
level, with two or three at the section/squad level.
Ammunition feed
Many light machine guns (such as the
Bren gun or the
M1918 Browning Automatic Rifle) were
magazine
A magazine is a periodical literature, periodical publication, print or digital, produced on a regular schedule, that contains any of a variety of subject-oriented textual and visual content (media), content forms. Magazines are generally fin ...
-fed. Others, such as the
Hotchkiss M1922, could be fed either from a
belt/
strip
Strip, Strips or Stripping may refer to:
Places
* Aouzou Strip, a strip of land following the northern border of Chad that had been claimed and occupied by Libya
* Caprivi Strip, narrow strip of land extending from the Okavango Region of Nami ...
or from a
box magazine
A magazine, often simply called a mag, is an ammunition storage and feeding device for a repeating firearm, either integral within the gun (internal/fixed magazine) or externally attached (detachable magazine). The magazine functions by holdi ...
. Modern light machine guns are designed to fire smaller caliber rounds and, as such, tend to be belt-fed (from a
container
A container is any receptacle or enclosure for holding a product used in storage, packaging, and transportation, including shipping.
Things kept inside of a container are protected on several sides by being inside of its structure. The term ...
attached to the gun) or from a detachable high-capacity
drum magazine
A drum magazine is a type of high-capacity magazine for firearms. Cylindrical in shape (similar to a drum), drum magazines store rounds in a spiral around the center of the magazine, facing the direction of the barrel. Drum magazines are contra ...
, but some, such as the
FN Minimi
The FN Minimi (short for ; "mini machine gun") is a Belgian 5.56mm or 7.62mm light machine gun, also classified as a squad automatic weapon developed by Ernest Vervier for FN Herstal. Introduced in the late 1970s, it is in service in more than ...
, will also accept standard rifle magazine feeding as an auxiliary measure when belted ammunition has been exhausted.
History
In 1903, French military theorists noticed that the
heavy machine gun
A heavy machine gun (HMG) is significantly larger than light, medium or general-purpose machine guns. HMGs are typically too heavy to be man-portable (carried by one person) and require mounting onto a weapons platform to be operably stable or ...
s of the day were of little use in infantry assaults. They determined that "the machine gun must learn to walk".
They researched the possibility of a light machine gun which could be carried by troops. A
marching fire tactic was theorised, using incidental suppressive fire, with the advancing troops considered a deadlier threat than the un-aimed bullets, causing the enemy to fall back. The prototype guns were not approved for production, and none were in service when
World War I
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...
began.
[ The French quickly brought the prototypes to mass production to boost the firepower of advancing infantry.
By the end of ]World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, light machine guns were usually being issued on a scale of one per fire team or squad
In military terminology, a squad is among the smallest of Military organization, military organizations and is led by a non-commissioned officer. NATO and United States, U.S. doctrine define a squad as an organization "larger than a fireteam, ...
, and the modern infantry squad had emerged with tactics that were built around the use of the LMG to provide suppressive fire
In military science, suppressive fire is "fire that degrades the performance of an enemy force below the level needed to fulfill its mission". When used to protect exposed friendly troops advancing on the battlefield, it is commonly called cover ...
.
Selected examples
The following were either exclusively light machine guns, had a light machine gun variant or were employed in the light machine gun role with certain adaptations.
See also
* Medium machine gun
A medium machine gun (MMG), in modern terms, usually refers to a belt-fed machine gun firing a full-powered rifle cartridge, and is considered "medium" in weight (). Medium machine guns are light enough to be infantry-portable (as opposed to ...
* Heavy machine gun
A heavy machine gun (HMG) is significantly larger than light, medium or general-purpose machine guns. HMGs are typically too heavy to be man-portable (carried by one person) and require mounting onto a weapons platform to be operably stable or ...
*Automatic rifle
An automatic rifle is a type of Self-loading rifle, autoloading rifle that is capable of fully automatic firearm, automatic fire. Automatic rifles are generally selective fire, select-fire weapons capable of firing in Semi-automatic firearm, semi ...
* Squad automatic weapon
* General-purpose machine gun
A general-purpose machine gun (GPMG) is an air-cooled, usually belt-fed machine gun that can be adapted flexibly to various tactical roles for light and medium machine guns. A GPMG typically features a quick-change barrel design calibered fo ...
* Assault rifle
An assault rifle is a select fire rifle that uses an intermediate cartridge, intermediate-rifle cartridge and a Magazine (firearms), detachable magazine.C. Taylor, ''The Fighting Rifle: A Complete Study of the Rifle in Combat'', F.A. Moyer '' ...
* List of machine guns
References
{{Authority control
*
Danish inventions