TRW Low Maintenance Rifle | |
---|---|
![]() The TRW LMR. Minor differences exist in the stock, handguard, and sights given the various prototypes made. | |
Type | Full-automatic fire only insurgency assault rifle |
Place of origin | ![]() |
Production history | |
Designer | Donald A. Stoehr (1927-2011) [1] |
Designed | February 1971 [2] |
Manufacturer | TRW Systems Group |
Unit cost | Specified cost of less than $130 (1971), [3] |
Produced | 1971—1973 |
No. built | fewer than 10. |
Specifications | |
Mass | Unloaded: 3.30 kg (7.3 lb) [4] Loaded: 3.64 kg (8.0 lb) [4] |
Length | 871 mm (34.3 in) [4] |
Barrel length | 493 mm (19.4 in) [5] |
Cartridge | 5.56×45mm NATO |
Action | Roller locked open bolt gas-operated long-stroke piston |
Rate of fire | 450 RPM Cyclic [4] |
Muzzle velocity | 3,248 ft/s (990 m/s) [4] [5] |
Effective firing range | 460 metres (1,510 ft) [4] |
Maximum firing range | 2,425 metres (7,956 ft) [5] |
Feed system | 20, 30-Round STANAG magazine [4] |
Sights | Rear: Two-position flip aperture Front: Adjustable post |
The TRW Low Maintenance Rifle or LMR was a proposed insurgency weapon designed by TRW Inc. (formerly Thompson Ramo Wooldridge) of the United States during the Vietnam War. The intent was to produce an easy-to-use and operate firearm which could be disseminated to insurgent forces supporting the United States' military interests. The design utilized the same 5.56×45mm NATO ammunition and STANAG magazines as the M16 rifle. It would have been equipped with the M6 bayonet along with its M8A1 scabbard.
Development began in 1971, and ceased in 1973 with the weapon never having been fielded.
The 5.56×45mm NATO is a rimless bottlenecked intermediate cartridge family developed in the late 1970s in Belgium by FN Herstal. It consists of the SS109, L110, and SS111 cartridges. On 28 October 1980, under STANAG 4172, it was standardized as the second standard service rifle cartridge for NATO forces as well as many non-NATO countries. Though they are not entirely identical, the 5.56×45mm NATO cartridge family was derived from and is dimensionally similar to the .223 Remington cartridge designed by Remington Arms in the early 1960s.
The AK-74 is an assault rifle designed by small arms designer Mikhail Kalashnikov in 1974. While primarily associated with the Soviet Union, it has been used by many countries since the 1970s. It is chambered for the 5.45×39mm cartridge, which replaced the 7.62×39mm cartridge of Kalashnikov's earlier automatic weapons for the Soviet armed forces.
The StG 44 is a German assault rifle developed during World War II by Hugo Schmeisser. It is also known by its early designations as the MP 43 and MP 44. The StG 44 was an improvement of an earlier design, the Maschinenkarabiner 42(H).
The Steyr AUG is an Austrian bullpup assault rifle chambered for the 5.56×45mm NATO intermediate cartridge, designed in the 1960s by Steyr-Daimler-Puch, and now manufactured by Steyr Arms GmbH & Co KG.
An automatic rifle is a type of autoloading rifle that is capable of fully automatic fire. Automatic rifles are generally select-fire weapons capable of firing in semi-automatic and automatic firing modes. Automatic rifles are distinguished from semi-automatic rifles in their ability to fire more than one shot in succession once the trigger is pulled. Most automatic rifles are further subcategorized as battle rifles or assault rifles.
The IWI Tavor, previously designated as the Tavor TAR-21, is an Israeli bullpup assault rifle chambered in 5.56×45mm NATO calibre, designed and produced by Israel Weapon Industries (IWI). It is part of the Tavor family of rifles, which have spawned many derivatives of the original design.
A magazine, or simply called mag, is an ammunition storage and feeding device for a repeating firearm, either integral within the gun or externally attached. The magazine functions by holding several cartridges within itself and sequentially pushing each one into a position where it may be readily loaded into the barrel chamber by the firearm's moving action. The detachable magazine is sometimes colloquially referred to as a "clip", although this is technically inaccurate since a clip is actually an accessory device used to help load ammunition into a magazine or cylinder.
The two most common assault rifles in the world are the Soviet AK-47 and the American M16. These Cold War-era rifles have been used in conflicts both large and small since the 1960s. They are used by military, police, security forces, revolutionaries, terrorists, criminals and civilians alike and will most likely continue to be used for decades to come. As a result, they have been the subject of countless comparisons and endless debate.
The Heckler & Koch HK33 is a 5.56mm assault rifle developed in the 1960s by West German armament manufacturer Heckler & Koch GmbH (H&K), primarily for export.
A STANAG magazine or NATO magazine is a type of detachable firearm magazine proposed by NATO in October 1980. Shortly after NATO's acceptance of the 5.56×45mm NATO rifle cartridge, Draft Standardization Agreement (STANAG) 4179 was proposed in order to allow NATO members to easily share rifle ammunition and magazines down to the individual soldier level. The U.S. M16 rifle's magazine proportions were proposed for standardization. Many NATO members, but not all, subsequently developed or purchased rifles with the ability to accept this type of magazine. However, the standard was never ratified and remains a "Draft STANAG".
The SG 540 is a 5.56×45mm NATO assault rifle developed in the early 1970s by Schweizerische Industrie Gesellschaft of Neuhausen, Switzerland as a private venture primarily destined for export markets and as a potential replacement for the 7.5×55mm Swiss SG 510 automatic rifle known as the Stgw 57 in Swiss service.
The Lithgow Small Arms Factory, or Lithgow Arms, is an Australian small arms manufacturing factory located in the town of Lithgow, New South Wales. It was created by the Australian Government in 1912 to ease reliance on the British for the supply of defence materials and is currently owed by Thales.
An assault rifle is a select fire rifle that uses an intermediate-rifle cartridge and a detachable box magazine. Assault rifles were first put into mass production and accepted into widespread service during World War II. The first assault rifle to see major usage was the German StG 44, a development of the earlier Mkb 42. While immediately after World War II, NATO countries were equipped with battle rifles, the development of the M16 rifle during the Vietnam War prompted the adoption of assault rifles by the rest of NATO. By the end of the 20th century, assault rifles had become the standard weapon in most of the world's armies, replacing full-powered rifles and submachine guns in most roles. The two most successful modern assault rifles are the AK-47 and the M16 designs and their derivatives.
The Magpul PDR is a prototype bullpup-style 5.56×45mm NATO carbine unveiled by Magpul Industries in 2006. Although halted in development as of 2011 it has garnered some attention, largely due to its "futuristic" appearance. The system consists of a gas-operated bullpup carbine intended to replace some submachine guns, M9 pistols and M4 carbines while still offering the rapid fire and range of an M4 carbine in an ultra compact firearm.
The .300 AAC Blackout, also known as 7.62×35mm, is an intermediate cartridge developed in the United States by Advanced Armament Corporation (AAC) for use in the M4 carbine. The cartridge yields increased performance in shorter barrels and effective subsonic performance for silencer use when compared to 5.56mm NATO. The .300 AAC Blackout uses standard 5.56mm NATO magazines and components with the exception of the barrel.
The IWI Galil ACE is a family of assault rifles and battle rifles originally developed and manufactured by Israel Weapon Industries (IWI). It is produced in three different calibres: 5.56×45mm NATO, 7.62×39mm and 7.62×51mm NATO.
The Bushmaster Arm Pistol was a 5.56×45mm NATO firearm, categorizeable as either a long pistol or compact carbine rifle, produced by the Gwinn Firearms Company, and later Bushmaster Firearms Inc. The firearm was a new design, having a rotating bolt combined with a long stroke gas piston system similar to the AK-47 rifle.
The B&T APC is a family of firearms produced and manufactured by B&T of Switzerland. A unique design feature of the APC is that more than 50% of all parts are interchangeable between the different calibres.
The SIG MCX is a family of firearms designed and manufactured by SIG Sauer, produced in both selective fire and semi-automatic only models, and features a short-stroke gas piston system, which is inherited from the earlier SIG MPX submachine gun. The MCX is available in rifle, carbine, short-barreled rifle, and pistol configurations.