The
SG 540 is a
5.56mm5.56x45mm NATO is a rifle cartridge developed in the United States and originally chambered in the M16 rifle. Under STANAG 4172, it is a standard cartridge for NATO forces as well as many non-NATO countries. It is derived from, but not identical to, the .223 Remington cartridge...
assault rifleAn assault rifle is a rifle designed for combat, with selective fire . Assault rifles are the standard infantry weapons in most modern armies, having largely superseded or supplemented larger and more powerful battle rifles such as the M14, FN FAL and the Heckler & Koch G3...
developed in the early 1970s by
Schweizerische Industrie GesellschaftSchweizerische Industrie Gesellschaft , or SIG, is the former name of SIG Holding AG a Swiss company that has been active in various businesses during its more than 150 years of operation. Since the year 2000 the Society has undergone strategic refocus, concentrating on its core compentence in...
(SIG, currently SAN Swiss Arms AG) based out of
NeuhausenNeuhausen am Rheinfall is a municipality in the canton of Schaffhausen in Switzerland...
,
SwitzerlandSwitzerland , officially the Swiss Confederation , is a federal republic consisting of 26 states named cantons, with Bern as the seat of the federal authorities...
as a private venture primarily destined for export markets and as a potential replacement for the 7.5mm SG 510
automatic rifleAutomatic rifle is a term generally used to describe a self-loading rifle chambered for a rifle cartridge, capable of delivering both semi- and fully automatic fire...
known as the Stgw 57 in Swiss service.
Work on a new generation of lightweight rifle using the intermediate 5.56mm round began at SIG in the 1960s and resulted in the somewhat unsuccessful
SG 530-1The SIG 530 was a Swiss assault rifle developed in the 1960s by Schweizerische Industrie Gesellschaft to take the then-new 5.56x45mm NATO round.-Development:...
design that employed a
gas-assistedGas-operation is a system of operation used to provide energy to operate autoloading firearms. In gas-operation, a portion of high pressure gas from the cartridge being fired is used to power a mechanism to extract the spent case and chamber a new cartridge. Energy from the gas is harnessed...
roller-delayed blowback operating mechanism which proved too complicated and expensive to manufacture.
The
SG 540 is a
5.56mm5.56x45mm NATO is a rifle cartridge developed in the United States and originally chambered in the M16 rifle. Under STANAG 4172, it is a standard cartridge for NATO forces as well as many non-NATO countries. It is derived from, but not identical to, the .223 Remington cartridge...
assault rifleAn assault rifle is a rifle designed for combat, with selective fire . Assault rifles are the standard infantry weapons in most modern armies, having largely superseded or supplemented larger and more powerful battle rifles such as the M14, FN FAL and the Heckler & Koch G3...
developed in the early 1970s by
Schweizerische Industrie GesellschaftSchweizerische Industrie Gesellschaft , or SIG, is the former name of SIG Holding AG a Swiss company that has been active in various businesses during its more than 150 years of operation. Since the year 2000 the Society has undergone strategic refocus, concentrating on its core compentence in...
(SIG, currently SAN Swiss Arms AG) based out of
NeuhausenNeuhausen am Rheinfall is a municipality in the canton of Schaffhausen in Switzerland...
,
SwitzerlandSwitzerland , officially the Swiss Confederation , is a federal republic consisting of 26 states named cantons, with Bern as the seat of the federal authorities...
as a private venture primarily destined for export markets and as a potential replacement for the 7.5mm SG 510
automatic rifleAutomatic rifle is a term generally used to describe a self-loading rifle chambered for a rifle cartridge, capable of delivering both semi- and fully automatic fire...
known as the Stgw 57 in Swiss service.
History
Work on a new generation of lightweight rifle using the intermediate 5.56mm round began at SIG in the 1960s and resulted in the somewhat unsuccessful
SG 530-1The SIG 530 was a Swiss assault rifle developed in the 1960s by Schweizerische Industrie Gesellschaft to take the then-new 5.56x45mm NATO round.-Development:...
design that employed a
gas-assistedGas-operation is a system of operation used to provide energy to operate autoloading firearms. In gas-operation, a portion of high pressure gas from the cartridge being fired is used to power a mechanism to extract the spent case and chamber a new cartridge. Energy from the gas is harnessed...
roller-delayed blowback operating mechanism which proved too complicated and expensive to manufacture. As a result, in 1969 SIG chose to dispense with the complex roller-delayed action opting instead for a design using the more robust and simple piston-operated
rotating boltRotating bolt is a method of locking found in gas operated, semi-automatic or selective fire firearms in which the bolt, upon contact with the breech, rotates and locks into place, being held in place by lugs attached to the breech or barrel extension.Upon closing, the bolt passes through the...
locking mechanism (derived from the
SovietThe Union of Soviet Socialist Republics was a constitutionally socialist state that existed in Eurasia from 1922 to 1991. The name is a translation of the , tr. Soyuz Sovetskikh Sotsialisticheskikh Respublik, abbreviated СССР, SSSR. The common short name is Soviet Union, from , Sovetskiy Soyuz...
7.62mmThe 7.62x39mm rifle cartridge was designed during World War II and first used in the SKS carbine by the Soviet Union.The cartridge was likely influenced by a variety of foreign developments, especially the pre-war German GeCo, 7.75x39mm experimental round, and possibly by the late-war German...
AKThe AK-47 is a selective fire, gas operated 7.62mm assault rifle developed in the Soviet Union by Mikhail Kalashnikov in the 1940s. Six decades later, the AK-47 and its variants and derivatives remain in service throughout the world...
assault rifle). This combination was to be successful and the rifle entered production as a family of weapons consisting of the base 5.56mm SG 540, the 7.62mm
SG 542 and the 5.56mm
SG 543 carbineA carbine is a firearm similar to a rifle or musket. Many carbines, especially modern designs, were developed from rifles, being essentially shortened versions of full rifles firing the same ammunition, although often at a lower velocity...
, where both 5.56mm weapons were designed for use with 5.56x45mm NATO M193 ammunition, while the SG 542—the full size
7.62x51mm NATOThe 7.62x51mm NATO is a rifle cartridge developed in the 1950s as a standard for small arms among NATO countries. Specifications for the 7.62x51mm NATO cartridge are not identical to the commercial .308 Winchester though they are safely interchangeable....
rifle cartridge. Production began between 1973–1974, but due to Swiss federal restrictions on firearms exportation it had to be carried out at the MANURHIN (
Manufacture de Machines du Haut Rhin) facility in
MulhouseMulhouse is a city and commune in eastern France, close to the Swiss and German borders. With 271,000 inhabitants in the metropolitan area in 2007 it is the largest city in the Haut-Rhin department, and the second largest in the Alsace region after Strasbourg...
,
FranceFrance , officially the French Republic , is a country located in Western Europe, with several overseas islands and territories located on other continents. Metropolitan France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean...
.
The SG 540 series has entered service with the armed forces of several countries in
AfricaAfrica is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people in 61 territories, it accounts for about 14.8% of the...
,
AsiaAsia is the world's largest and most populous continent, located in the eastern and northern hemispheres. It covers 8.6% of the earth's total surface area and with approximately 4 billion people, it hosts 60% of the world's current human population.Asia is traditionally defined as part of the...
and
South AmericaSouth America is the southern continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere...
as well as numerous law enforcement and security agencies. In 1988, the nationally-owned
PortuguesePortugal , officially the Portuguese Republic , is a country located in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of mainland Europe and is bordered by the Atlantic Ocean to the west and south and by Spain to the north and east...
defense manufacturer
INDEPINDEP - Indústrias Nacionais de Defesa, EP , originally Fábrica do Braço de Prata , is a defense industry company owned by the Portuguese Government....
purchased rights to license build the SG 543 carbine. Currently both the SG 540 and SG 542 are only manufactured in
ChileChile, officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
, under license by
FAMAEFAMAE is a Chilean government-owned weapons producer. Its products are used by the Chilean armed forces and the police. The company produces among others the FAMAE SAF submachine gun, FAMAE FD-200 sniper rifle, Cohete Rayo rocket launcher and FAMAE revolver. FAMAE is funded, in addition to Chile,...
for the Chilean Armed Forces. Based on the SG 540, FAMAE developed a 9mm
submachine gunA submachine gun is a firearm that combines the automatic fire of a machine gun with the cartridge of a pistol, and is usually between the two in weight and size...
version of the weapon known as the
SAFThe FAMAE SAF is a submachine gun produced since 1993 by FAMAE , the Chilean government small arms factory...
.
Operating mechanism
The SG 540 is an air-cooled,
gas-operatedGas-operation is a system of operation used to provide energy to operate autoloading firearms. In gas-operation, a portion of high pressure gas from the cartridge being fired is used to power a mechanism to extract the spent case and chamber a new cartridge. Energy from the gas is harnessed...
,
selective fireA selective fire firearm fires semiautomatically and at least one automatic mode by means of a selector depending on the weapons design. Some selective fire weapons utilize burst fire mechanisms to limit the maximum or total number of shots fired automatically in this mode...
assault rifle that fires from a
closed boltA semi or fully-automatic firearm which is said to fire from a closed bolt is one where, when ready to fire, a round is in the chamber and the bolt and working parts are forward...
position. SIG designers used a long-stroke piston-driven action (with the recoil spring wrapped around the piston rod itself) and an adjustable gas regulator with three settings: "0"—used to launch
rifle grenadeA rifle grenade is a grenade that uses a rifle based launcher to permit a longer effective range than would be possible if the grenade was thrown by hand...
s, "1"—used in normal operating conditions and "2"—used in extreme environmental conditions or in the presence of heavy fouling. The firearm is locked into battery by means of a
rotating boltRotating bolt is a method of locking found in gas operated, semi-automatic or selective fire firearms in which the bolt, upon contact with the breech, rotates and locks into place, being held in place by lugs attached to the breech or barrel extension.Upon closing, the bolt passes through the...
which features two heavy
steelSteel is an alloy consisting mostly of iron, with a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most cost-effective alloying material for iron, but various other alloying elements are used such as manganese, chromium, vanadium, and tungsten...
locking lugs. The bolt head is rotated by a control cam riding in a helical guide slot machined into the bolt carrier. When a shot is fired, propellant gases from the barrel are fed into the gas cylinder located above the barrel and impart rearward pressure on the piston rod, which drives the bolt carrier back. After a certain amount of free travel built into the system to allow the projectile to depart the barrel, residual gas pressures in the bore drop to a safe level, allowing the breech to be opened. The cam slot in the bolt carrier proceeds to actuate the camming stud in the bolt, rotating the bolt head out of engagement with the locking abutments in the receiver. The spent cartridge casing is extracted by a claw extractor contained in the bolt assembly while a protrusion on one of the internal bolt carrier guide rails in the upper receiver acts as the fixed ejector, removing the casing through a port on the right side of the receiver housing.
Features
The rifle is hammer-fired and has a fire control selector mechanism that is also the safety (lever in the "S" position—indicates the gun is safe, "1"—semi-automatic fire, "3"—3-round burst and "20"—fully automatic fire). The SG 540 is fed from either 20 or 30-round staggered box magazines. After the last round is fired, a hold-open tab in the magazine engages the bolt catch that locks the bolt in its rear (open) position. A bolt release button is located on the left side of the receiver.
The
rifledRifling is the helix-shaped pattern in the barrel of a gun or firearm, which imparts a spin to a projectile around its long axis. This spin serves to gyroscopically stabilize the projectile, improving its aerodynamic stability and accuracy....
barrel is fitted with a
flash suppressorA flash suppressor, also known as a flash guard, flash eliminator, flash hider, or flash cone, is a device attached to the muzzle of a rifle or other gun that reduces the visible signature of the burning gasses that exit the muzzle...
, which is also used to attach
rifle grenadeA rifle grenade is a grenade that uses a rifle based launcher to permit a longer effective range than would be possible if the grenade was thrown by hand...
s and a
bayonetA bayonet is a knife-, dagger-, sword-, or spike-shaped weapon designed to fit on, over or underneath the muzzle of a rifle barrel or similar weapon, effectively turning the gun into a spear. It is a close quarter battle combat or last-resort weapon.-History: The origins of the bayonet are...
. The iron sights consist of a hooded foresight that can be corrected in elevation and an adjustable (windage only), rotating rear drum that contains four apertures with settings for firing at: 100, 300, 400 and 500 m. The receiver top surface can be used to mount adapters enabling the use of optics.
The SG 540 series come equipped with either a fixed buttstock or a side-folding metal skeleton stock. Another standard feature is a folding
bipodA bipod is a support device that is similar to a tripod or monopod, but with two legs. It provides significant stability along two axes of motion -Firearms:...
which is stowed under the handguard when not in use. The fixed stock, pistol grip and handguard are all made of high-strength polymers to reduce overall weight. In order to minimize costs, metal stamping was employed in the production process.
Variants
Differences between the SG 542 and the SG 540 are mainly the result of adopting a more powerful, full-size rifle cartridge. The SG 542 also uses normally 20/30-round box magazines (5 and 10 magazines were also manufactured) but the sights were modified with a 600 m setting in addition to the 100, 300 and 500 m sight drum positions.
The SG 543 carbine is a shortened variant of the SG 540 that has been modified with a short barrel, a shorter gas cylinder and piston rod as well as a different handguard and sights with 100, 200, 300 and 400 m firing range positions. The SG 543 lacks the integral bipod of the SG 540/542 and the reduced barrel cannot be used to fire rifle grenades.
The SG 540 served as the basis for the
SG 541 prototype, which would later become the
SG 550The SG 550 is an assault rifle manufactured by Swiss Arms AG of Neuhausen, Switzerland;...
that entered service with the Swiss Armed Forces as the Stgw 90 (
Sturmgewehr 90).
Additionally, two semi-automatic variants were manufactured by MANURHIN between the late 1970s and the early 1980s specifically for the
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, the Caucasus Mountains , and the Black Sea to the southeast...
an civilian market: called the
SIG Manurhin F.S.A. and the
SIG Manurhin C.S.A.. These rifles were chambered in
.222 RemingtonThe .222 Remington aka the Triple Deuce/Triple Two/Treble Two is a centerfire rifle cartridge introduced in 1950, and was the first commercial rimless .22 cartridge made in the United States...
and
.243 WinchesterThe .243 Winchester is a popular sporting rifle cartridge. Initially designed as a varmint round, it is now more frequently used on medium to large game such as whitetail deer, mule deer, pronghorn, wild hogs, and even black bear and caribou....
respectively. Both were available with either 30-round or reduced 5-round magazines, and the option of a folding or fixed stock. The unusual chambering for this type of military-style rifle was an attempt to comply with regulations in certain European countries imposing restrictions on the civilian ownership of "military" cartridges such as the
5.56x45mm NATO5.56x45mm NATO is a rifle cartridge developed in the United States and originally chambered in the M16 rifle. Under STANAG 4172, it is a standard cartridge for NATO forces as well as many non-NATO countries. It is derived from, but not identical to, the .223 Remington cartridge...
/
.223 RemingtonThe .223 Remington is a sporting cartridge with almost the same external dimensions as the 5.56x45mm NATO military cartridge. The name is pronounced either two-two-three or two-twenty-three...
or
7.62x51mm NATOThe 7.62x51mm NATO is a rifle cartridge developed in the 1950s as a standard for small arms among NATO countries. Specifications for the 7.62x51mm NATO cartridge are not identical to the commercial .308 Winchester though they are safely interchangeable....
/
.308 WinchesterThe .308 Winchester is a rifle round and is the commercial version of the military 7.62x51mm NATO centerfire cartridge. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65. Winchester branded the cartridge and introduced it to the commercial...
.
FAMAEFAMAE is a Chilean government-owned weapons producer. Its products are used by the Chilean armed forces and the police. The company produces among others the FAMAE SAF submachine gun, FAMAE FD-200 sniper rifle, Cohete Rayo rocket launcher and FAMAE revolver. FAMAE is funded, in addition to Chile,...
of Chile manufacture a Designated Marksman Rifle variant as the
FD-200The FAMAE FD-200 is a semi automatic designated marksman rifle of Chilean origin and is chambered in the 7.62x51mm NATO round.It saw a very limited production run in the early 2000s, and was based upon their license-made SIG SG 540 assault rifle action and frame, although all mechanics were...
chambered in 7.62x51mm NATO with an accurised barrel.
Users
: Uses the SG 542 variant.: Manufactured by FAMAE in accordance with a license from SIG (SG 540, SG 542, FD-200).: SG 540.: SG 540.: Used by EPIGN, GIPN and
RAIDRecherche Assistance Intervention Dissuasion or RAID. RAID is like the GIPN a local SWAT unit of the Police Nationale with more menpower and equipment. Its responsibility areas are Paris and the suburbs as well as "Plan Piratair" , nuclear sites, the Channel Tunnel, the trains, and other strategic...
.: The
Portuguese ArmyThe Portuguese Army is the ground branch of the Portuguese Armed Forces which, in co-operation with other branches of the Portuguese military, is charged with the defence of Portugal...
ComandosFor the denomination of "commando" see commando; for the Argentine special operations unit see Amphibious Commandos Group; for other special forces with "Commando" in their names see list of special forces units....
and Special Operations Forces use the SIG SG 543, some 600-700 carbines are thought to be used.
http://enciclopedia.com.pt/images/com1x.jpghttp://static.flickr.com/95/268059914_8872ffa240.jpghttp://www.exercito.pt/portal/exercito/_specific/public/ueo/EP/SIGSG543.jpghttp://www.aoe.pt/images/BEOE/20040605%20AOE%20I%2015.jpg
See also
- SG 510
The SIG SG 510 or Sturmgewehr 57 is an automatic rifle manufactured by Schweizerische Industrie Gesellschaft of Switzerland...
, the previous service rifle but still in service.
- SG 550, Switzerland's current service rifle.
- Assault rifle
An assault rifle is a rifle designed for combat, with selective fire . Assault rifles are the standard infantry weapons in most modern armies, having largely superseded or supplemented larger and more powerful battle rifles such as the M14, FN FAL and the Heckler & Koch G3...
- Gun politics in Switzerland
Gun politics in Switzerland are unique in Europe. The personal weapon of militia personnel is kept at home as part of the military obligations. This, in addition to liberal gun laws and strong shooting traditions, has led to a very high gun count per capita. Switzerland has one of the highest gun...