PANAGYURISHTE, (BM) – Along with the Kalashnikov assault rifle, the M16 assault rifle has become one of the most popular twentieth-century rifles in the world. M16 was adopted by many countries in Europe, Asia, Africa and America, and due to the characteristic color of the stock and forearm received the nickname “black rifle”.
The assault rifle (automatic) M16 appeared due to the development of the famous designer Eugene Stoner (Eugene Stoner). In the course of research conducted by the U.S. Department of Defense in the 1940-1950s, it was concluded that there was a need to switch from .30 (7.62 mm) weapons to .22 (5.56 mm) weapons.
In 1957, the Armalite Division of the Fairchild Aircraft Corp from the U.S. Army received a proposal to develop an automatic .22 (5.56 mm) caliber rifle, with a small mass, capable of breaking a standard army helmet at a range of 500 meters. As part of this program, Armalite’s designer Eugene Stoner begins developing a new rifle based on his earlier development — the AR-10 rifle with a caliber of 7.62 mm.
At the same time, engineers from Sierra Bullets and Remington, in partnership with Armalite, are starting to develop a new 5.56 mm live cartridge based on .222 Remington and .222 Remington Magnum hunting cartridges. The new cartridge was originally named .222 Remington Special, but soon received the designation – .223 Remington (5.56×45 mm).
In 1958, Armalite Division introduced, for testing the U.S. Army, developed by Eugene Stoner, a 5.56-mm rifle under the designation AR-15.
As a result of reducing the cartridge in the new rifle, the total weight of the weapon was reduced, the ammunition was increased and the recoil force was reduced. Also, in the design of the AR-15, Stoner used lightweight aluminum alloys and fiberglass, which made the rifle one of the lightest in the world. This weapon was a bit unusual. It was striking that the sights were on a special frame for carrying weapons. With this design, the butt was located on the same line with the axis of the bore, which helped to minimize recoil force, and led to a decrease in the vertical displacement of the bullet during firing.
However, during the tests revealed a number of problems with the reliability and accuracy of fire. In 1959, the new rifle was sent for revision, but by Colt’s Patent Firearms Manufacturing Company, which completely redeems the rights to its design from Armalite. And Y. Stoner himself leaves Armalite and goes to work in Colt, where he continued to work on his rifle.
However, in 1959, the army lost interest in the development of Stoner and tried to get weapons with a caliber of 6 mm under the program “Personal Special Purpose Weapons” (SPIW).
However, the U.S. Air Force, which is interested in obtaining compact weapons to equip airfield security units, is keen to purchase 8,000 rifles for the US AF Strategic Air Command security forces to replace the obsolete carbines M1 and M2.
In 1962, the Advanced Research Projects Agency (ARPA) purchased 1,000 rifles from Colt and sent them to South Vietnam for testing in real-life combat. Despite the theoretical advantages, practical application in the conditions of hostilities immediately revealed numerous shortcomings. Suppliers said that the rifle does not require much maintenance, and the rifle was quite moody.
For reasons of economy, the U.S. Army did not order enough kits to clean weapons during initial purchases.
In addition, again for reasons of economy, poorly selected gunpowder (when creating cartridges for the new rifle, Dupont type IMR gun was used, and the U.S. Army in the manufacture of cartridges replaced it with the standard gunpowder used to equip cartridges 7.62x51mm NATO) too much soot, because of which the sleeve tightly stuck in the chamber. The sleeve had to be knocked out with a ramrod, which during the fighting led to disastrous results.
The flaws identified in Vietnam forced the developers to reconsider the design of the “black rifle.” Chrome plating of the chamber and the bore increased corrosion resistance and facilitated cleaning.
The type of cartridge powder was changed to a better one, giving less carbon deposits. A more viscous lubricant was introduced because standard gun oil in tropical climates was unsuitable. 20 cartridge stores were replaced by 30 cartridge stores. This increased the weight of the rifle, but on the other hand equalized the indicators with Kalashnikovs of Soviet and Chinese production.
In 1963, Colt received a contract for the production of 19,000 M16 rifles for the US Air Force and 85,000 XM16E1 rifles for the US Army. The M16 rifle was nothing more than the original AR-15 with the corresponding marking (Property of US Govt – Property of the US Government, etc.).
The XM16E1 rifle differed from the AR-15 / M16 by the presence of a shutter ramp (“forward assist”), which had the appearance of a large button on the right side of the receiver.
In 1964, the U.S. Air Force officially adopted the M16 rifle, and the U.S. Army adopts the XM16E1 rifle as a limited standard weapon to fill a temporary (as it was then thought) niche between the discontinued 7.62-mm M14 rifle and the upcoming SPIW weapon .
After the military found the SPIW program wrong, their eyes were again turned to the development of Stoner. In 1966, Colt received a government contract for the supply of 840,000 rifles, totaling nearly 92 million US dollars.
On February 28, 1967, the US Army officially adopted the XM16E1 rifle under the designation “US Rifle, 5.56mm, M16A1.” In 1981, Colt developed a variant of the M16A1 rifle adapted to the 5.56×45 mm NATO SS109 cartridge (an improved version of the 5.56×45 mm cartridge developed by the Belgian company Fabric National and adopted as a single cartridge for NATO armies) and transfer it to the Army for testing USA under the designation M16A1E1.
This rifle differed from the M16A1 in a thicker and heavier barrel with a rifling pitch of 1: 7 (in the previous model the rifling pitch was 1:12), improved sights, a new forearm and stock, and also replacing the continuous fire mode (bursts) with a cut-off mode queues after 3 shots.
In 1982, the M16A1E1 rifle received the official designation “US Rifle, 5.56mm, M16A2”, and in 1983 and 1985 it was adopted by the Marine Corps and the US Army in exchange for the M16A1.
In 1994, the US Armed Forces began to receive new variants of the M16 – the M16A3 and M16A4 rifles, which have the so-called “flat” (“flat top”) receiver boxes, in which the integrated carrying handle has been replaced with a Picatinny rail designed to fit a wide variety of sights, including a removable carrying handle with sights of the type M16A2.
Otherwise, the M16A4 rifle is identical to the M16A2, while the M16A3 is also different in that instead of cutting off 3 shots, there is a fire mode in bursts of any length (as on M16A1).
Technically, the M16 / AR-15 series rifles are automatic or semi-automatic weapons with air-cooled barrel, powered from detachable box magazines and gas engine-based automation. Fire is conducted from a closed shutter.
Eugene Stoner gas vent automation does not have a gas piston in its traditional sense. Powder gases are discharged through an opening in the barrel wall and are discharged through a stainless steel gas tube into the receiver. The rear end of the gas tube before the shot enters a special nozzle (gas key), mounted on top of the shutter frame.
At the time of the shot, the powder gases pass through the gas tube and through nozzles enter the cavity inside the shutter frame. This annular cavity is located around the shutter shank and on the front side is bounded by a thickened part of the shutter, and on the back – by the wall of the shutter frame. The gas pressure inside this cavity forces the shutter frame to begin to move backward, relative to the initially stationary shutter.
This movement with the help of a figured groove in the bolt frame and the leading pin on the bolt that enters into it rotates the bolt, releasing its combat stops (number 7) from engagement with the barrel shank. After the bolt disengages from the barrel, the entire bolt group (bolt and bolt frame) continues to move backward under the influence of residual gas pressure in the chamber and due to the inertia of these parts.
With this movement, the spent sleeve is removed from the barrel and thrown out and the return spring located in the butt is compressed. Under the influence of the return spring, the bolt group returns forward, feeding a new cartridge into the barrel and locking the barrel at the end of the movement by turning the bolt.
After all the cartridges in the magazine have been used up, the bolt group automatically remains in the rear position due to the presence of a bolt delay in the mechanism, which is switched on automatically by the magazine feeder and turned off manually using the button on the left side of the receiver.
The T-shaped cocking handle, located in the rear of the receiver above the butt, and does not move when firing. Starting with the M16A1 (XM16E1) model, rifles have a shutter ramper on the right side of the receiver that is designed to manually close the shutter if there is not enough return spring force (for example, the chamber is clogged). The rammer has the form of a button with a dog on the opposite end, interacting with the notches on the right side of the shutter frame.
The case ejection window is closed by a spring-loaded dust-proof shutter, which automatically opens when the shutter is cocked. And starting with the M16A2 model, behind the window for ejecting cartridges, a protrusion reflector appeared, designed to provide the possibility of comfortable shooting from the left shoulder.
For the M16A1, which did not have such a device, the US Army had a special detachable reflector, which, if necessary, was mounted on the weapon in a couple of minutes.
Trigger trigger, quite simple in design. USM operating modes are selected using a three-position (on military weapons) or two-position (on civilian) switch located on the receiver on the left, above the pistol grip. The switch for military weapons has the following positions: “safe” (fuse), “semi” (single shots), “auto” (automatic fire, M16A1) or “burst” (fire with a cut-off of 3 shots for M16A2).
The receiver is made of two halves – the upper (upper receiver) and lower (lower receiver). Both halves are machined from aluminum forged billets (some commercial models have cast aluminum receiver cases). The connection of the two halves occurs with the help of two transverse pins – front (rotary – pivot pin) and rear (disassembling – takedown pin). For incomplete disassembly, the rear pin is squeezed out from left to right with any suitable object, including a cartridge, and then the receiver “breaks” around the front pin, after which you can remove the bolt group and the handle for loading, and inspect and clean the weapon . For further disassembly, the front pin is extruded in the same way, and the receiver is disassembled into two parts.
Sights M16A1 include a round fly on the base of the gas chamber, closed laterally with two “ears”. The diopter pillar is a flip-flop, L-shaped, designed for a range of 250 and 400 meters, and is located in the carrying handle.
The front sight has the ability to adjust in height, and the rear sight has a mechanism for introducing lateral corrections (only to bring weapons to normal combat). On M16A2, the front sight is generally similar to the front sight of M16A1, however, it has a rectangular cross section.
The whole is also diopter, flip, however, the range corrections are introduced using the drum under the whole, and two apertures are designed for different shooting conditions – in good light (lower) and in low light (high).
Instead of an integral handle, the M16A3 and M16A4 models have a guide rail for attaching various sights of the Picatinny type (MilStd -1913). If necessary, a removable carrying handle with sights identical to the M16A2 rifle can be mounted on this guide.
Weapons are supplied from box-shaped double-row stores. Initially, the stores were aluminum, with a capacity of 20 rounds. Later aluminum and steel magazines with a capacity of 30 rounds appeared. In addition, there is a significant selection of stores of various capacities produced for commercial sale – from 7 and 10-cartridge for civilian weapons, to 40-cartridge box-shaped and 100-120 cartridge drum (including 100 American-made Beta-C 100-cartridge double drums and 120 -Patron drums made in China).
Flame arresters on the earliest M16 models are three-slit, with slots open forward, on M16A1 – four-slit, with slots closed in front, on M16A2 – five-slit. A bayonet-knife model M7 or M9 can be installed on the arrester.
On rifles M16A1 and M16A2, the installation of a 40-mm single-shot grenade launcher M203 is possible. The grenade launcher is installed under the barrel of the rifle instead of the standard forend. For firing from a grenade launcher, special additional sights are installed on the rifle.
The forend, pistol grip, and buttstock are made of high impact black plastic. Handguard on M16A1 and more early rifles – a triangular cross-section, of two non-interchangeable halves, left and right. On the M16A2, the forearm is of circular cross section, of two interchangeable halves, the upper and lower. Inside the forend has aluminum heat-shielding liners.
The butt of M61A2 is slightly longer than that of M16A1. In the butt plate of the butt there is a door covering the compartment for accessories for cleaning and caring for weapons.
The rifle is equipped with a removable rifle belt.
Compared to its main enemy, the Soviet Kalashnikov rifle, the M16 rifle on the world arena of twentieth-century weapons had greater accuracy and accuracy in firing single shots, was more comfortable and convenient to use. On the other hand, the M16 required much more thorough care, better ammunition. In reliability under especially severe conditions (pollution, dusting), the AKM also exceeded the M16.
One of the main advantages of the construction of Yu. Stoner should be recognized as its exceptional flexibility. Due to the modularity of the design, which actually consists of two large modules – the “upper” (upper part of the receiver, barrel, gas outlet, forend, sights, bolt group) and the “lower” (lower part of the receiver, trigger mechanism, buffer with return spring, pistol grip, butt), provided the ability to very quickly reconfigure the rifle.
So, on one “lower” part that meets the standards, you can install the upper parts with trunks of very different lengths (from 250 to 610 mm), caliber (.22LR, 7.62×39 mm, 9×19 mm, 10 mm Auto, .50AE and many others, not counting native 5.56×45 mm), with an integral or removable carrying handle. This is especially important for consumers in the civilian and police markets.
In addition to the US armed forces, army-style M16 rifles were adopted by the US police and were widely exported. They were used by the armies of more than 70 states (including special forces).
A significant amount of the M16 was put into service with Israel. The production of the M16 rifle under license was carried out in the Philippines and in South Korea. The Canadian company Diemaco has established the production of licensed options for M16 under the designations C7 and C8 for the Canadian armed forces and for export.
Since 1988, FN Manufacturing Co, the American division of the Belgian concern FN Herstal, has become the main supplier of M16A2 rifles for the US Armed Forces, and Colt continued to manufacture AR-15 / M16 rifles for the civilian and police markets, as well as for export.
Also, the production of civilian and police modifications of the AR-15 rifle under various designations was established by dozens of companies in the United States, in particular, such as Armalite, Bushmaster, Hesse, Les Baer, Olympic Arms, Wilson Combat, and many others.
In addition, clones of AR-15 began to be produced in China at state-owned enterprises of NORINCO under the designations “Model 311” (self-loading version) and “CQ” (version with the possibility of automatic fire).
Follow us everywhere and at any time. BulgarianMilitary.com has responsive design and you can open the page from any computer, mobile devices or web browsers. For more up-to-date news from us, follow our YouTube, Reddit, LinkedIn, Twitter and Facebook pages. Do not miss the chance to subscribe to our newsletter. Subscribe and read our stories in News360App in AppStore or GooglePlay or in FeedlyApp in AppStore or GooglePlay
Subscribe to Google News