During the Vietnam War, the US Army had helped the armed forces of friendly countries and provide them with a variety of armaments and equipment. Nevertheless, often such deliveries were associated with excessive and unjustified spending or it is impossible to. To solve these problems, it was proposed to create a special version of the small arms - the most simple and inexpensive automatic rifle with a sufficiently high performance. This sample of the weapon remained in history under the name TRW Low Maintenance Rifle.
In the early seventies, the Pentagon experts have proposed the original idea, Allows you to get the desired results in the sphere of military-technical cooperation with foreign countries, but at the same time dramatically reduce costs to help them. Until now, the friendly armies or armed groups in order by the transmission of armaments and equipment consisting on the types of weapons, often differ high price. Especially for the implementation of such new supplies offered to create the most simplified and cheap, but sufficiently effective automatic rifle.
A new project was launched in 1971 year, and soon identified the basic requirements for prospective arms. Firstly, Rifle had to have a minimum cost, due to simplicity of design and production. Simultaneously with this product was different high performance. The first recipient of the new rifles were to be the army of South Vietnam, who had to fight in a difficult climate. Consequently, Weapon was different resistance to high humidity and other factors characteristic. Finally, should simplify the operation of weapons, with him to cope poorly trained fighters. Besides, This reduces the risks, associated with the wrong logistics and lack of timely bringing up the necessary materials.
The last requirement to the rifle was issued in the name of the program. A new sample of the weapon was working designation Low Maintenance Rifle - «rifle with a reduced need to service". For convenience, involving a reduced LMR. Since the rifle has not been put into service, she was not given an official army designation, and she remained in history under the working title.
Rifle TRW Low Maintenance Rifle with Bipod.
LMR to the competition were presented several preliminary projects, and soon the customer chose the most successful. According to Pentagon specialists, best looking project by TRW Systems Corp. (former Thompson Ramo Wooldridge). curious, that the main activity of the organization at that time was the space technology. However, this did not prevent her to try his hand in the field of small arms. In just a few years, TRW has developed and proposed several new models of this type, including simplified rifle.
Project Low Maintenance Rifle from TRW is based on several main ideas. To simplify the design was planned to use a number of used engineering solutions, and in addition, should give up certain functions. production costs have been reduced through the use of cheap materials, simple technology, as well as some pre-built components. operational nature of the claim decided to perform with the help of various designs covering all the main parts.
View from the other side.
Main, though not the largest part of the new weapons is a receiver, joined by all other details. It was mounted on the front of the tubular barrel shroud with perforation and a gas engine. On the elongate shank boxes offered to install the butt. One way to simplify the design became TN. linear layout. Cover and receiver assembly is actually a long metal tube variable section with certain external devices. It has consistently placed the barrel and movable gate. Instead of the traditional rear cover on the receiver placed the butt of a special design. Under the front of the receiver was a small enclosure with details of the trigger.
The rifle had rifled barrel caliber 5,56 mm 493 mm (88 calibres). The chamber was designed for the standard intermediate munition 5,56h45 mm NATO. On the right side of the barrel, near the muzzle, It was gas escape hole. It connects the barrel to the cylinder of the gas engine, which is secured aboard the barrel jacket. Inside the cylinder, a piston was a long stroke, as well as its return spring. Such an arrangement of a gas engine freed up space inside the receiver and to simplify the construction of weapons.
The gas piston and long gate frame constituted one large item. Its front cylindrical portion received energy propellant gases, and flat rear responsible for gate drive. It is also a cocking lever. And, as some other automatic rifles, the handle was brought forward in relation to the shutter. Between the slide frame and shutter cover plate was placed, defending the receiver box from dirt.
Common types of weapons. Sheet of instruction manual
The receiver had a square cross-section, which affected the shape of the shutter. Last performed in the form of a massive block with rounded side surfaces and a number of different grooves and holes. The longitudinal bore of the shutter moving spring loaded firing pin. The anterior third shutter, up and down, It provided for a pair of locking clips. When moving the bolt forward, they were pulled out of him and enter into the slots of the receiver.
Rifle TRW LMR received not the most usual means of ammunition, that, however, will simplify the design of weapons. On the left side of the receiver is a small reception shop horizontal shaft. Cartridges from the latter were to come to the chambering line, and liner proposed to throw through a window in the right wall. When you move the shutter overlapped sliding cover forward window, that prevents dirt. The basic version of the rifle perspective was to use an intermediate cartridge 5,56h45 mm and standard magazines for M16 rifle.
Gunsmiths of TRW Systems considered, that the full trigger mechanism with a choice of modes of fire makes weapons too complex and expensive. In connection with this rifle was firing bursts with an open shutter, and fire control facilities offered to take the finished sample. The source of the necessary components become serial gun M60. He borrowed the entire fire control unit in a housing with a handle and trigger details.
rifle scheme. Figure out the instruction manual
T-system with the trigger, sear and fuse placed directly under the receiver box and secure with the help of standard pins. Trigger before the shot could block the gate in the rearmost position. Pressing the trigger led to its displacement forward, chambering a new cartridge and a shot. Translator fire was out, and because the weapon could lead only automatic fire. However, with proper skill and training of a fighter could shoot and single.
Interesting, what LMR rifle received two non-automatic fuse type. One was part of the trigger and blocking the descent, and the second input of the gas engine. At the front position of the shutter arm recharge rotated clockwise and entered into the groove, Hold it in place. This blocked the movement of the piston and of the slide.
Experienced rifle equipped with a simple sighting devices. Above the muzzle of the barrel and the receiver placed cylindrical tubular base. they, in its turn, front sight and sight were simplified design. On the back of the support have established a semi-circular cap with changeover entirely. In one position it provided aiming at distances up to 300 yards, in the other - from the 300 to 500 yards.
"The rifle is a reduced need to service" has a very specific ergonomics. Hold it suggested using a plastic pistol grip and the barrel casing. Also of particular butt it was developed. It performed as a square tube with stamped shoulder rest of a pair of vertical plates. Tube butt worn on the shank of the receiver and the fixed pin. At stud had a ring-sling swivel belt. A second ring placed near the muzzle.
Partially disassembled rifles.
Customer doubted the ability of future operators to provide proper care for a weapon, and it should take into account at the design stage. To reduce maintenance requirements applied a significant number of chrome parts. This coating protects the powder from the coke barrel, bolt group and other aggregates, in contact with the powder gases. In some parts instead of conventional liquid lubricants proposed to apply a film of dry lubricant. Such a coating does not require special maintenance. After 2000 shots offered to clean off the remains of grease and apply in their place a new film.
From the perspective cheapening rifle could use a variety of additional devices. The front part of the gas tube, Stand to the right of the front sight, It proposed to strengthen the bayonet type M6. Besides, rifle can be equipped with a folding bipod. This product was attached just behind the muzzle. During the tests, the authors of the project also experimented with different designs muzzle attachment, flame arresters and brake-compensator.
Rifle TRW LMR assembly had a length 34,3 inch (1045 mm). After setting the length of the bayonet increased to 40 inches (1,22 m). The weapon turned out not too high, but the location of the store side of the mine led to an increase of its width. Rifle without ammunition weighed 7,26 pound (3,3 kg). Equipment store weighed slightly less 350 g.
Shutter and drummer.
Gas engine and trigger one mode of operation it possible to obtain good characteristics martial. Relatively long barrel ensures acceleration to bullet 990 m / s. Technical rate determined in 450 rounds per minute. In practice, the maximum rate of fire is limited 120 rounds per minute. The need for a long flame with a limited ammo further reduced rate. Maximum range exceeded 2,25 km, but effectively limits the total 460 m.
In terms of principles of automatic rifle Low Maintenance Rifle resembled some guns. The specific arrangement of weapons and forced to think about the other weapons of the past samples, the design of which is also taken into account the need to maximize simplify and reduce the cost of.
Placing the store in the receiver, the shooter had to pull the gas piston lever and bring it to the extreme rear position, after which the shutter was fixed sear, and the piston back to its original place. When you press the trigger the shutter freed, I went ahead, shall be sent to the cartridge and locking trunk. Moving by inertia drums ignited cartridge. Powder from the bore gases enter into a gas engine and causes the piston to go back, sliding bolt group. Depending on the position of the trigger or sear, Rifle make a new shot or getting on the squad.
One of the main goals of the project was to reduce the cost of the series rifles. At the design stage it has been determined, that the mass production of a single product TRW LRM will cost the customer in 130 dollars - less than 800 dollars at current prices. for comparison, M16 rifle serial while cost about 300 dollars.
Designing a new weapon took only a few months and was completed in the same 1971 year. Soon TRW Systems company started production of experimental rifles, which should test and present military. known, that the prototypes of the new weapon in a certain way different from each other. As the test finished products and refining project in the construction of new rifles were made various minor changes. Besides, tested various embodiments retrofitting. The main ideas, technologies and approaches are not changed and are common to all the prototypes.
Least, one of the prototypes of the product TRW LMR was calculated under special cartridge. Instead of the standard intermediate cartridge with the "traditional" bullet he had to use the XM126 ammunition with piercing arrow-bullet. However, this rifle version is not too far from the base.
Development work on "the necessity of a rifle with a shortened service" lasted for about two years. Testing and debugging rifles were made to 1973 of the year, when the military decided to give up an interesting project. For all its benefits, Project cheap and easy rifle TRW Low Maintenance Rifle no longer make sense. Change the military-political and strategic situation, as well as the emergence of reasonable alternatives put an end to this weapon.
Couple museum rifles. Products are of some construction details and the composition of additional equipment.
AT 1973 the outcome of the current year of the war was already clear, and the United States began to withdraw the army from Vietnam. In the foreseeable future, new armed conflicts not anticipated, and American forces, looks like, not had to supply the Allied massive and cheap weapon simplified design. Besides, By this time, the gun industry has completed the finishing M16 rifle, and now it could be produced in large quantities for themselves, and foreign partners.
In this situation, an automatic rifle, Low Maintenance Rifle from TRW Systems companies had no real future. The Pentagon decided not to waste time, energy and money on a project with a questionable future, and therefore ordered to stop work. By this time the company-developer did not have time to perform all the required work and get ready for serial production. only a few prototypes have collected over two years, and after 1973 LMR year were not made. Some of these products have been preserved and are now museum pieces.
The LMR project was based on the desire to make a weapon with acceptable specifications, suitable for fast and cheap help the allied. Despite certain difficulties, technical part of this problem has been solved. The company TRW Systems has been able to create the most simple automatic rifle, suitable for low cost mass production. However, even before the design work the need for such weapons missing. The project did not lead to the desired results, but still he took his place in the history of American small arms.
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