Armalite AR-10
| Armalite AR-10 | |
|---|---|
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| general information | |
| Civil name: | AR-10 |
| Country of operation: | 1958–1985 Sudan ; 1960–1976 Portugal |
| Developer / Manufacturer: | ArmaLite , Artillery Equipment |
| Development year: | 1955-1956 |
| Manufacturer country: | USA , Netherlands |
| Production time: | 1956 to 1961 |
| Weapon Category: | Rapid fire rifle |
| Furnishing | |
| Overall length: | 1050 mm |
| Total height: | 528 mm |
| Weight: (unloaded) | 4.3 kg |
| Barrel length : | 508 mm |
| Technical specifications | |
| Caliber : | 7.62 × 51 mm NATO |
| Possible magazine fillings : | 20 cartridges |
| Ammunition supply : | Trapeze magazine |
| Fire types: | Single , continuous fire |
| Visor : | Open sights |
| Closure : | Rotating head lock with 7 lugs |
| Charging principle: | direct gas pressure charger |
| Lists on the subject | |
The AR-10 is a rapid-fire rifle that is unusually light for the 7.62 × 51 mm NATO cartridge used . This was mainly achieved through the use of an aluminum alloy for the weapon housing. In order to keep the recoil within limits despite the low weight of the weapon, a direct-acting gas system was used. Special ergonomics have also been used for better recoil control. These recoil-reducing features were later adopted by the AR-15 and are still used today in its successors, the M16A4 and M4A1 .
As with the AR-15, all weapons based on the AR system that use rifle ammunition rather than medium cartridges are often incorrectly referred to as AR-10.
history
The AR-10 was developed by Eugene Stoner for the ArmaLite Division of Fairchild Engine & Airplane Corporation.
The first prototype was set up for the 7,62 × 63 mm (.30-06) cartridge ; it had the in-house designation "X01" and was very similar to the Johnson MG .
Like the following models, prototype 2 was set up for the cartridge 7.62 × 51 mm NATO (.308 Winchester) and bore the designations "X02" and "AR-10-1001". Instead of an open sight, this prototype had a handle with a built-in telescopic sight and shaft parts made of fiberglass-reinforced plastic.
Prototype 3 again had a handle with an open sight and a muzzle compensator ; it was marked "X03" and "AR-10A".
Prototype 4 was labeled “AR-10” (although it was called “AR-10B” in-house) and “ARMALITE”. With this prototype, the AR-10 had almost reached its final shape. The cocking handle was now on top of the housing within the carrying handle and the upper and lower parts of the housing were connected with a hinge so that the rifle could be opened for cleaning and dismantling. To save weight, the housing was made of an aluminum alloy, the shaft parts were made of fiberglass-reinforced plastic (the piston was filled with plastic foam to increase stability) and the barrel consisted of a steel inner tube that was screwed into a barrel extension, which was also made of steel and with a Jacket pipe made of a light metal alloy. Five rifles (serial numbers 1001 to 1005) were made of this type.
In 1956 one of these rifles (serial number 1002) was officially tested at the State Armaments Factory Springfield Arsenal; however, the compound barrel failed in this test - it tore open on the side and slightly injured the shooter's hand. Stoner therefore made a new steel barrel (which was fluted to save weight). With this, the AR-10 passed the further tests, but was not accepted.
This was followed by the rifle with the serial number "S1004", which was the first to be provided with the new company logo (the Pegasus) and whose handle was set up for mounting a telescopic sight. All of the following rifles were designated as "AR-10".
Strangely enough, the AR-10 was followed by the rifle with the serial number "1048", which in turn was marked as AR-10A. This was the last rifle made by Armalite itself.
In preparation for a possible series production, Armalite hired engineer L. James Sullivan, who prepared the production plans for the series model. He added two changes to the design: On the one hand, the lock received sealing rings made of metal, which ensured better utilization of the propellant gases, and on the other hand, he moved the gas tube from the left barrel side to the barrel top.
However, Armalite only produced 48 AR-10B and AR-10; the series production took place later under license from the Dutch state enterprise Artillerie-Inrichtingen (AI) in Zaandam. In 1956 there were negotiations between Fairchild and the Dutch aircraft manufacturer Fokker. As part of these negotiations, Richard Boutelle, then President of Fairchild, introduced the AR-10. An agreement was reached with AI about license production of the AR-10 in the Netherlands. Since various armies were looking for a new rifle at the time, it was hoped that larger numbers of the AR-10 could be sold.
Since the requirements of the various armies required that the rifle could also fire rifle grenades, further changes to the AR-10 were required. The muzzle compensator, which was the key to controllable automatic fire from such a light rifle, had to give way to a flash hider, which also served as a rifle grenade device. In addition, the barrel of the AR-10 had to be significantly reinforced in order to withstand the considerable loads when firing rifle grenades. The AR-10 was significantly heavier than originally planned and lost another advantage over its competitors.
It was tested u. a. in Austria, the Federal Republic of Germany, the Netherlands and South Africa, was shortlisted every time, but failed because the potential customer had to be offered a too long delivery time due to the not yet available production capacities.
Cuba and Sudan acquired some AR-10s, and more went to Burma. Portugal acquired 1200 pieces. For tests by the Finnish Army, five AR-10s with a caliber of 7.62 × 39 mm were produced. In addition to the rifle version, AI developed a carbine version with a shorter barrel, a group support rifle with a fixed barrel and magazine feed, and a light machine gun with a belt feed and a barrel that can be quickly exchanged.
Despite everything, the hoped-for success did not materialize. In 1959, Fairchild decided not to renew the license agreement. Production at AI ended in 1961 after around 9600 AR-10s had been produced.
Fairchild then negotiated with Colt about licensing the AR-10 and AR-15; After successful negotiations, Colt began preparations for series production of the AR-10A (corresponding to the rifle with the serial number 1048). A sales tour with the AR-10 and AR-15 through the Far East, however, revealed that there was an interest in the AR-15, but not in the AR-10. As a result, Colt stopped work on the AR-10 and concentrated on the AR-15.
technology
The AR-10 is a shooting , air-cooled gas pressure charger with a fire selection device; the ammunition is supplied from detachable box magazines .
The rifle consists of two main assemblies: the upper receiver with barrel, bolt assembly, handle, handguard and rear sight and the lower receiver with trigger mechanism, piston, firing pin as control valve, with spring barrel, spring and buffer, grip and magazine slot. The upper and lower parts of the housing are connected by two cross bolts. If the rear bolt - located above the handle - is pushed out, the rifle can be opened to e.g. B. to remove the closure group.
The closing spring with the buffer, which also serves as a closing spring guide, is located in a tube at the end of the lock housing. The foamed piston is pushed onto this tube. A spring lock prevents the recoil spring unit from snapping forward when the weapon is open. The locking group slides partially into the recoil spring tube during the reloading process.
The barrel and slide of the AR-10 are in a straight line with the end of the spring in the piston; In the shoulder stop, the recoil is directed directly and without leverage into the shooter's shoulder, which reduces the rifling of the weapon. However, this arrangement requires a line of sight that lies high above the core axis of the barrel.
The combined fire selection / safety lever is on the left side of the weapon above the handle, so that it can be reached with the thumb without having to take your hand off the handle. The lever has three positions (front - continuous fire, down - safe, rear - single fire ). This was changed later (front - safe, below - single fire, rear - continuous fire). The slide catch release is also on the left. The AR-10 has a bolt catch that holds the bolt carrier in the rear position when the magazine is empty and is activated by the magazine feeder. The magazine release is located on the right side of the weapon in front of the trigger; it can be operated with the trigger finger without changing your grip. The magazine falls freely from the weapon when the trigger is pressed. The tensioning lever , which does not move with the retracting locking group, is located within the handle and is similar in shape to a trigger. The lower part of the trigger guard can be opened as a "winter trigger" to facilitate use with gloves.
The locking system with rotating head is based on the Johnson rifle (which, however, is a recoil loader with a short recoil) and, unlike contemporary rifles, does not lock in the housing, but directly in the barrel, making it possible to manufacture the housing from an aluminum alloy . The gas system is based on contemporary military self-loading rifles (Ag m / 42, MAS-49), but the propellant gases in the AR-10 are not simply introduced into a recess in the front face of the bolt carrier and blow it directly backwards.
With the AR-10, some of the propellant gases produced when the cartridge is fired is fed through a gas extraction hole on the left barrel side through a tube and another hole in the housing side into the hollow bolt carrier. There is no gas regulator.
The lock is slidably mounted in the lock carrier; both parts work together like the piston and cylinder of an internal combustion engine. The propellant charge gas flows into the breechblock carrier, which is sealed towards the front by the breechblock and thus pushes the breechblock carrier backwards. The bolt carrier slides backwards against the pressure of the recoil spring; Since the bore in the housing side and the corresponding bore in the side of the bolt carrier are no longer in contact after a short backward movement, no more gas can flow in, but the push is sufficient to move the bolt carrier back completely.
Lock and lock carrier are loosely connected to one another by a control pin; the control pin sits in a cross hole in the bolt and a control cam in the bolt carrier. When the bolt carrier moves backwards, the bolt remains in its front, locked position until the control pin rotates through it - following the control cam - so that the locking lugs emerge from the abutments on the barrel extension. In this position the bolt releases three holes on the right side of the bolt carrier through which the gas (through the ejection window) can escape. At the end of the backward movement, a buffer reduces the impact of the bolt carrier on the end of the housing.
On August 14, 1956, Eugene Stoner filed a patent application with the US Patent Office on this gas mechanism; the corresponding patent was granted on September 6, 1960 under the number 2,951,424. The bolt head with radially arranged locking lugs was not part of the patent, since Mel Johnson already had a US patent on it; Since Johnson was also working as a consultant for ArmaLite at the time, he probably did not object to its use in the AR-10.
Rebirth of the AR-10
In 1990, Eugene Stoner and C. Reed Knight Jr. of Knight Manufacturing Company (Knight's Armament Company) teamed up with the goal of reviving the concept of the AR-10. Stoner planned that the new rifle would become the most accurate semi-automatic rifle for the 7.62 × 51 mm NATO cartridge. While the concept of the AR-10 remained unchanged, improvements such as the M16A2, then in production, were to be incorporated into the new rifle to make it better than the old AR-10. Since it was supposed to combine properties of AR-10 and AR-15, the new rifle was named SR-25 (Stoner Rifle 25) - 25 for 10 + 15 and "Stoner" because the brand name ArmaLite was in the hands of a legal successor old company located.
The SR-25 was manufactured as a Match Rifle (barrel length 24 inches), Lightweight Match Rifle (barrel length 20 inches) and RAS Carbine (barrel length 16 inches); and are equipped with the KAC RAS forend with four M1913 mounting rails. The Match and Lightweight Match are also available with a round fore-end without mounting rails. All three versions shoot only semi-automatically. All variants have a so-called "flat-top receiver", i. H. Instead of the handle, which also functioned as a rear sight base, there is a mounting rail according to the M1913 standard ( Picatinny rail ) on the top of the housing .
A variant of the Lightweight Match Rifle was introduced by the US Navy SEALs as the "Rifle 7.62 mm Mk11MOD 0"; this sniper rifle is also used by other special forces of the US armed forces. The M110 introduced into the US armed forces is also based on the SR-25.
In 1994, Mark Westrom, President of Eagle Arms Incorporated, began developing a self-loading rifle based on the AR-10, which he named "M-10". In 1995, Eagle Arms Inc. acquired the naming rights to ArmaLite and renamed the rifle the AR-10. Like the SR-25, the new AR-10 is based on the old rifle and includes modern improvements. The AR-10 (T) version has a flat-top receiver and is available with a 24-inch barrel and as a carbine version with a 16-inch barrel with a muzzle compensator. The AR-10A4 version has a flat-top receiver and is available with a 20-inch or 16-inch barrel (each with a muzzle compensator). The version AR-10A2 is similar to the AR-10A4, but has a fixed handle instead of the mounting rail on the housing. The AR-10B intended for the collector's market corresponds to the AR-10A2 with a 20-inch barrel; carries the old ArmaLite logo (the Pegasus) and has brown (instead of black) barrel parts to be more similar to the old AR-10.
literature
- Gary Paul Johnston, Thomas B. Nelson: The World's Assault Rifles. Ironside International Publishers, Lorton (VA), USA 2010, ISBN 978-0-935554-00-7
- R. Blake Stevens, Edward C. Ezell: The Black Rifle: M16 Retrospective. Collector Grade Publications, Cobourg / Ontario, Canada 1987, ISBN 0-88935-115-5 .
- Christopher R. Bartocci: Black Rifle II: The M16 into the 21st century. Collector Grade Publications, Cobourg / Ontario, Canada 2004, ISBN 0-88935-348-4 .
Web links
- Patent US2951424 - Gas Operated Bolt and Carrier System . google.com. Retrieved May 20, 2012.
Individual evidence
- ↑ Leroy Thompson: Weapon Volume 37 The M14 Battle Rifle . Osprey Publishing, Oxford 2014, ISBN 978-1-4728-0255-2 (English).
- ↑ Günter Wollert, Reiner Lidschun, Wilfried Copenhagen : Rifle Guns Today (1945-1985) Volume 2 . 5th edition. Brandenburgisches Verlagshaus, Berlin 1998, ISBN 3-89488-057-0 .
- ^ R. Blake Stevens & Edward C. Ezell: The Black Rifle, M16 Retrospective . 2nd Edition. Collector Grade Publications, Ontario, Canada 1992, ISBN 978-0-88935-115-8 (English).