The SOCIMI Weapon Systems
by J.M. Ramos

The peak of the accelerating cold war between Russia and the United States and heightened terrorists activities around the world in the 1980s resulted in the formation of many new military arms producers, not only in the USA but almost every corner of the globe. Highly industrialized countries like Germany, Belgium, Switzerland and Italy led the way in small arms development in western Europe. Among these old world countries, Italy can be considered the pillar and pioneer of arms developers in that part of the continent having produced weapons of war since the rise of the Roman empire. It is no surprise then that even after many hundred of years had gone by, Italian craftsmen still produce some of the most remarkable weapon systems for today’s modern centurions. Italy’s most historical achievement in the small arms field was no doubt the adoption of its Beretta 92F pistol by the US Armed Forces, beating all contenders the world’s greatest arms producers had to offer. While the firm of Beretta S.p.A. remained the flagship of Italy’s old world gunmakers, it was eventually joined by new and innovative companies that strictly developed and produced weapons for law enforcement and military roles.

In l982, the firm of Societa Costruzioni Industriali Milano S.p.A. (SOCIMI), a highly respected railway construction product developer and producer entered the field of small arms manufacturing. Having no previous know-how in the arms manufacturing industry, its first step was to seek outside assistance. In creating its weapon systems, SOCIMI took the expertise of veteran arms maker Luigi Franchi S.p.A. of Brescia and formed the SOCIMI group. There were three weapons developed and manufactured by the company namely the Model 821 9mm SMG, the AR 832/FS (7.62x51mm NATO) and AR-831 5.56x45mm NATO) assault rifles. These weapons were jointly designed by Franchi’s Defence System Division and Socimi engineers. All weapons are produced by three factories managed by SOCIMI namely the Binasco plant, Arluno plant and Sardinia plant. Both Binasco and Arluno factories are based in Milano while the Sardinia plant is located in Sassafras. Briefly, the submachine gun model was produced by Franchi S.p.A. until all the tooling are completed to produce the weapons at all three SOCIMI factories.

By mid 1982, SOCIMI completed the first prototype of their 9mm submachine gun. Tooling for producing the gun commenced immediately and production begun soon after. The production gun was designated the Model 821 and was offered for commercial sale in the early fall of 1983. At first glance the M821 closely resembled the famed Israeli Uzi submachine gun. When the Socimi SMG was introduced, the Uzi’s popularity was still at its peak, and the US secret service is still carrying it to protect the president. The battle-proven credentials of the Israeli gun was another factor that influenced the Italian engineers to create a shorter, lighter and more refined version of the Uzi that adapted to ultra-modern manufacturing technology.

The SOCIMI M821 design and operating principle is close to that of the Uzi submachine gun. The 3-position sliding type fire selector, the grip-mounted magazine catch and grip safety are all derived from the Uzi, as well as the wrap-around bolt, cocking handle and removable barrel system. It also retained the simple blowback operation and fixed firing pin ignition principle. Field stripping procedure is also the same as that of the UZI.

Despite all the similarities noted with the UZI, the M821 has some distinctive features of its own. Most notable of these differences include a side-folding metal stock, finger groove grip pattern, a heavy-duty recoil buffer system and a slightly different trigger mechanism incorporating a double sear arrangement for optimum safety. To attain maximum lightness, the SOCIMI submachine gun utilized machined light alloy forgings, instead of the heavy sheet metal stampings found on the Uzi, in the manufacture of the weapon’s receiver and grip frame, making the M821 about a pound lighter than the Israeli gun. This lightness also allows the weapon to be fired with one hand if need be. The M821 is also designed to accept laser aiming devices and a silencer by substituting a threaded barrel for the standard part. The M821 is ideally suited for commando units as well as urban and jungle warfare. Although the M821 was offered in the international arms market until l990, it is unknown to date if it has ever gained commercial success or was ever adopted by any nation. It is however a remarkable modernized version of the famed Uzi submachine gun that deserves a closer look and serious consideration by countries that are still engaged in jungle warfare or anti-terrorist operations.

The second weapon developed and produced by SOCIMI is the AR-831 assault rifle chambered for the 5.56x45mm NATO cartridge. Once again in designing the AR-831 assault rifle, SOCIMI chose to improve upon an existing popular design. In this case, the Armalite-designed Ml6 assault rifle was chosen as a basis. While externally resembling the US Ml6 rifle, there were some mechanical improvements incorporated in the AR-831 to make the weapon more trouble free when exposed to extreme climatic conditions such as mud, snow, sand and dust. Arguably, the weakness of the US combat rifle is its gas system, which is easily affected by entry of foreign matter. To make the Ml6 work reliably, the gas tube must be maintained on a regular basis to ensure that any obstruction in the tube is removed, allowing unrestricted flow of gas pressure in order to unlock the action during cycle of operation.

The Italian engineers at SOCIMI realized the shortcomings of the US service rifle and came out with an improved M16-type rifle in the form of the AR-831. The new rifle, which they developed in 1985, utilized an AK47-type gas piston, which is directly mounted at the top of the bolt carrier. The bolt and bolt carrier assembly are identical to that of the M16, as well as the recoil spring, recoil spring guide, magazine catch and hold-open device. The cocking handle and trigger mechanism are slightly different in format but function and connect in the same manner. The standard 20- and 30-round M16 magazines are used. There is a slight variation in plastic furniture design, as well as the angle of the pistol grip that is of finger groove pattern. The 3-position fire selector is derived from the original M16 and can only be manipulated conveniently by right-handed shooters. There is no bolt-assist incorporated into the AR-831. It is not needed due to its superior AK47 gas piston operating system. Additionally, the weapon is equipped with a gas regulator, which also controls the rate of fire, and also permits the use of grenades of various kinds. A folding stock variant of the AR-831 is also offered patterned after the Belgian FN FAL Para carbine. In the fixed stock version, the recoil spring is housed inside a large tube that also doubles as a connecting base for the plastic buttstock (M16-style). In the Para, the recoil spring is assembled inside the gas piston like on the AK-47 design.

In l987, a more modernized and streamlined version of the SOCIMI 5.56x45mm assault rifle was introduced. It was designated as the model AR-871. The new refined version is a selective-fire weapon using a gas-operated rotating bolt that locks directly into the barrel extension. The rifle is produced in various formats with a variety of fire selection systems, allowing semiautomatic or full-automatic fire, semiautomatic or three-shot burst or semiautomatic-only. The weapon retained the original straight stock configuration along with a long stroke bolt cycle that provided mild recoil. The rifle is light and rugged with majority of the components being made of light alloy forgings and hi-impact resistant polymer materials. Other materials are high tensile steel. The cocking handle is now positioned on the left side of the receiver frame. The original design had the cocking handle on the top rear of the receiver behind the carrying handle. The magazine release is now ambidextrous on the new version. The barrel is chrome lined and the muzzle is designed to accommodate grenade launching. Both the original AR-831 and the latest version AR-871 assault rifles can be field stripped quickly and easily without the need of tools starting with the removal of the rear connecting pin (like the M16) and hinge open the action to pull out the bolt and carrier assembly. However, it can be easily stripped in minutes (except trigger group) of its sub-components (buttstock, handguard, gas piston and flash hider groups) using only the rim and point of a cartridge as a tool if a more detailed cleaning is required.

The third and final weapon developed and produced by SOCIMI is the AR-832/FS assault rifle chambered for the 7.62x51mm NATO cartridge. Like its 5.56x45mm cousin, it shares the same basic mechanical design characteristics and materials in its overall construction. It is externally different from the AR-831 utilizing a conventional rifle sight rather than the hi-placement sighting plane of the M16 genre. The rifle has certain external features of the Para FAL rifle with similar folding stock and cocking handle positioned in the left side of the receiver. The gas regulator system is also a derivative of the FAL but with the combination of the Kalashnikov gas piston principle. The mating of two battle proven systems resulted in an extraordinary rifle with outstanding simplicity, rugged overall construction and very light weight with its light alloy and plastic furniture construction. Like its 5.56x45mm variant, the AR 832/FS is equipped with a gas regulator that controls rate of fire as well as providing grenade launching of various types. Field stripping provision on the 7.62x51mm NATO rifle is the same as the smaller AR-831. While full production of the assault rifle series commenced as far back as the later part of the l980’s, there is not much information as to how the SOCIMI battle rifles fared in terms of commercial sales or if any country has ever considered them for adoption. In examining the design characteristics of all the weapons developed and produced by the Socimi Group, there is no doubt that they represent logical design characteristics combining what has proven to work and making the best of it.


Via San Calimero n. 3
20122 Milano
Via del Serpente, 12
25020 Brescia,

This article first appeared in Small Arms Review V7N3 (December 2003)
and was posted online on September 27, 2013


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