M60 machine gun

The M60 (formally the United States Machine Gun, Caliber 7.62 mm, M60) is a family of American general purpose machine guns firing 7.62x51mm NATO cartridges from a disintegrating belt of M13 links.Introduced in 1957, until recently it remained in use in every branch of the U.S military and still serves in other armed forces. Its manufacture and continued upgrade for military and commercial purchase continues into the 21st century though it has been replaced or supplemented in most roles by other designs, notably the M240 (US nomenclature for the FN MAG-58) in U.S service.Major variations include the M60E1 (an improved version that did not enter production), the M60E2 (a version designed to be used from fixed mounts as a co-axial for armored vehicles or in helicopter armament systems), the M60E3 (a lightweight version) and the M60E4 (another improved version, designated Mk 43 Mod 0 by the U.S. Navy). The M60C was adopted for use on fixed mounts on aircraft. The M60D differed from the base model by employing spade grips, a different sighting system, and lacking a forearm. It was typically employed as a door gun on helicopters or as a pintle mounted weapon as on the Type 88 K1 tank. There are many smaller variants among each type, between makers of the firearm, and over time.

M60 machine gun
Class Manportable
Type Machine Guns
Manufacturer U.S. Ordnance–Defense Systems and Manufacturing
Origin United States of America
Country Name Origin Year
United States of America 1957
Country Name Operational Year Retirement Year
United States of America View
ManufacturerName Production From Production To Quantity
U.S. Ordnance–Defense Systems and Manufacturing View

The M60 is a gas-operated, air-cooled, belt-fed, automatic machine gun that fires from the open-bolt position and is chambered for the 7.62×51 mm NATO cartridge. Ammunition is usually fed into the weapon from a 100-round bandolier containing a disintegrating, metallic split-link belt.

The design drew on many common concepts in firearms manufacture of the period, such as stamped sheet metal construction, belt feed (a modified mechanism for belt feed from the MG42 with a single pawl), quick barrel replacement, a pistol grip and stock, and a Semi bullpup design similar to the FG 42 (much of the action occupies the weapon's stock). The M60's operating system of an operating rod turning a rotating bolt was inspired by the FG 42, which was based on the much earlier Lewis Gun. The M60 was even constructed with a secondary assisting firing pin spring that is used in the FG 42 in semi-automatic mode even though it is actually unnecessary in the M60 (which operates only in full automatic mode). The M60's gas operation is unique, and drew on technical advances of the period, particularly the White "gas expansion and cutoff" principle also exploited by the M14 rifle. The M60's gas system was simpler than other gas systems and easier to clean.

The M60 was designed for mass production, just like the MG42 it was based on. While the M1919 required much machining for its large, recoil operated internal mechanisms, the M60's stamped sheet receiver had a gas operated, carrier-cammed bolt mechanism; the same type of mechanism was used on the Lewis machine gun.

The straight-line layout allowed the operating rod and buffer to run directly back into the buttstock and reduce the overall length of the weapon.

As with all such weapons, it can be fired from the shoulder, hip, or underarm position. However, to achieve the maximum effective range, it is recommended that a bipod-steadied position or a tripod-mounted position be used and fired in bursts of 3–5 rounds. The weapon is heavy and difficult to aim when firing without support, though the weight helps reduce the felt recoil. The large grip also allowed the weapon to be conveniently carried at the hip. The gun can be stripped using a live round of ammunition as a tool.

The M60 is often used with its own integrated bipod or with the M122 tripod. The M60 is considered effective up to 1,100 meters when firing at an area target and mounted on a tripod; up to 800 meters when firing at an area target using the integral bipod; up to 600 meters when firing at a point target; and up to 200 meters when firing at a moving point target. United States Marine Corps doctrine holds that the M60 and other weapons in its class are capable of suppressive fire on area targets out to 1,500 meters if the gunner is sufficiently skilled.

Originally an experimental M91 tripod was developed for the M60, but an updated M2 tripod design was selected over it which became the M122. The M122 would be itself replaced in the 2000s (decade) by a new mount, in time for the M60 to also be used with it.

The M60 machine gun began development in the late 1940s as a program for a new, lighter 7.62 mm machine gun. It was partly derived from German guns of World War II (most notably the FG 42 and the MG 42), but it contained American innovations as well. Early prototypes, notably the T52 and T161 bore a close resemblance to both the M1941 Johnson machine gun and the FG 42. The final evaluation version was designated the T161E3. It was intended to replace the M1918 Browning Automatic Rifle and M1919A6 Browning machine gun in the squad automatic weapon role, and in the medium machine gun role. One of the weapons tested against it during its procurement process was the FN MAG.

The U.S. Army officially adopted the T161E3 as the M60 in 1957. The decision to adopt the M60 instead of foreign designs, like modified versions of the proven German MG42 or the still-unproven FN MAG, was largely due to strict Congressional restrictions requiring preference be given to the designs of US arms manufacturers (even if a superior design was available from foreign sources) primarily out of desire to avoid paying licensing fees, but also out of a strong bias in favor of domestic products.

The M60 later served in the Vietnam War as a squad automatic weapon with many U.S. units. Every soldier in the rifle squad would carry an additional 200 linked rounds of ammunition for the M60, a spare barrel, or both. The up-gunned M113 armored personnel carrier ACAV added two M60 gunners beside the main .50 caliber machine gun, and the Patrol Boat, River had one in addition to two .50 cal mounts.

During the Vietnam War, the M60 received the nickname "The Pig" due to its bulky size. Vietnam's tropical climate harshly affected weapons, and the M60 was no exception. Its light weight made the gun damage easily and critical parts like the bolt and op rod wore out quickly. Even so, soldiers appreciated the gun's handling, mechanical simplicity, and effective operation from a variety of firing positions. Navy SEALs used M60s with shorter barrels and no front sights to reduce weight further. Some SEALs had feed chutes from backpacks to have a belt of thousands of rounds ready to fire without needing to reload.

In the 1980s, the M60 was partially replaced by the M249 Squad Automatic Weapon within Army infantry squads. Their new doctrine with the weapon reduced the general purpose machine gun role in favor of portability and a greater volume of fire. Soldiers disliked the new strategy, as even though the lighter SAW made movement faster, in firefights the larger 7.62 mm round is preferred. In defensive roles, the M60 has better accuracy and a longer range to keep the enemy back. The M60 was retained in the vehicle mounted role and the general-purpose role due to its greater power and range compared to the 5.56 mm M249.

In U.S. Marine Corps service, concerns about the M60's reliability, weight, and the high round counts of many M60s in service prompted the adoption of the M60E3 to replace most original M60s in infantry units. The M60E3 was five pounds lighter than the original M60. It included a forward pistol grip and had the bipod mounted to the receiver rather than the barrel. The weapon still was not durable and its performance was reduced.

In the early 1990s, Saco addressed Navy Special Warfare requirements to develop a retrofit parts package for the machine gun. Called the M60E4, it was more reliable and durable than the M60E3, had a “duckbill” flash suppressor, and a shorter and thicker positive lock gas cylinder extension. NAVSPECWAR units began to receive it in late 1994, when it was designated the MK43 Mod 0.

In January 1994, the U.S. Army began the Medium Machine Gun Upgrade Kit program. The only two competitors were M60 and M240 versions. Saco offered an "enhanced" M60E3 with product improved parts and FN offered its M240 coaxial gun with a buttstock, bipod, and other infantry features. As such, both weapons were upgrade kits of weapons already in service. 18 guns of each were tested until December 1995. There were two main performance areas: Mean Rounds Between Stoppages (MRBS-jams) and Mean Rounds Between Failures (MRBF-parts breaking). 50,000 rounds were fired through both guns. The M60 had 846 MRBS and 1,669 MRBF, compared to the M240's 2,962 MRBS and 6,442 MRBF. As a result, the M240 was declared the winner and accepted into infantry service. Although the M60 was lighter, had better balance, was more controllable, and there were many in the inventory, it did not work reliably enough.

Starting with Ranger Battalions, the U.S. Army began adopting and modifying M240 variants to replace their remaining M60s in the early 1990s. The M240 is several pounds heavier than the M60, and has a longer barrel and overall length, but it is more reliable in use and testing. However, the M60 uses a much simpler gas system that is easier to clean when care is taken during reassembly. This advantage is obviated since the gas tube is wired shut with lockwire to prevent the weapon from disassembling itself from vibration in hard use.

The M60 continues to be used in the 21st century by U.S. Navy SEALs and as a door gun on U.S. Army helicopters. It was the main 7.62 mm machine gun by some U.S. special operations forces to the late 1990s. As of 2005, it is used by the U.S. Coast Guard, U.S. Navy, and some reserve units. The M60 is generally being phased out.

Type General-purpose machine gun
Place of origin United States of America
Service history
In service 1957–present
Used by Algeria
Australia
Bolivia
Bosnia-Herzegovina
Cambodia
Chile
Colombia
Costa Rica
Czech Republic
Democratic Republic of Congo
Denmark
Dominican Republic
El Salvador
Egypt
Fiji
Ghana
Greece
Haiti
Honduras
Italy
Indonesia
Jordan
Lebanon
Liberia
Lithuania
Luxembourg
Malaysia
Morocco
Netherlands
New Zealand
Nicaragua
Panama
Peru
Philippines
Poland
Portugal
Republic of Korea
Saint Vincent and the Grenadines
Senegal
Sudan
Taiwan
Thailand
Trinidad and Tobago
Tunisia
Turkey
Uganda
United Kingdom
United States
Venezuela
Wars Vietnam War
Laotian Civil War
Cambodian Civil War
Cambodian–Vietnamese War

Salvadoran Civil War
The Troubles
Persian Gulf War
War in Afghanistan
Iraq War
Cambodian–Thai border stand-off
Colombian armed conflict
Insurgency in the Philippines
Bougainville Civil War
2013 Lahad Datu standoff
various others
Production history
Designed Late 1940s–1957
Manufacturer Saco Defense
U.S. Ordnance
Unit cost $6,000
Produced 1957–present
Specifications
Weight 10.5 kg (23.15 lb)
Length 1,105 mm (43.5 in)
Barrel length 560 mm (22.0 in)
Cartridge 7.62×51mm NATO
Caliber 7.62 mm (0.308 in)
Action Gas-operated, short stroke gas piston, open bolt
Rate of fire 500–650 rounds/min (rpm)
Muzzle velocity 2,800 ft/s (853 m/s)
Effective firing range 1,200 yd (1,100 m)
Feed system Disintegrating belt with M13 Links
Sights Iron sights

End notes