Italy’s Next Generation Rifle: The ARX 160
The authors were invited to attend the presentation ceremony of the new Beretta ARX 160 Assault Rifle from the world’s oldest firearm manufacturer still in business and test fire the weapon on an Italian Army firing range located in Nettuno, a city facing the Mediterranean Sea, roughly 35 miles south of Rome. This location is well known in America for being, together with Anzio, the beachhead and battle site for the Allied Forces landing of Operation Shingle in World War II.
The ARX 160 is currently delivered in a hard case containing all accessories. A special waterproof and floating soft bag is also available for maritime operations. It is a gas operated, select-fire assault rifle, with a piston action located above the barrel, which fires from a closed bolt.
The weapon’s design is streamlined and stylish, with a dark, flat grey colored Polymer body and is totally different from the sharp and edgy lines of the well known AR70/90. It loosely resembles the lines of the FN SCAR, especially in the stock design, but the rifle is lighter, more compact and structurally very different.
We tested the final version of the weapon that was assembled in a small scale production line that will be ramped up for full scale production in a few months. This version was preceded by a long series of prototypes, built patiently pursuing the best results and performance, taking seriously in account vital feedback from military beta testers, including operators in actual combat scenarios.
The ARX 160 has been engineered from the start to be extremely flexible and modular so as to tailor its individual performance for the mission or task at hand. There are two barrel lengths available at this time for the weapon: 16-inch (standard) and 12-inch (defined, by Beretta, “for special operations”). A 20-inch barrel has been tested, and a 16-inch HB with Match grade rifling should be available shortly to fill in a DMR role.
Both the 16-inch and 12-inch barrels have a flash hider/compensator fitted with 5 radial cuts, plus other 4 smaller cuts, indexed so as to aid in controlling muzzle climb when shooting full auto. Barrels are chrome lined and have a 1:7 twist, optimized for the SS109/M855 ball, and L110/M856 tracer ammunition. Barrels are user changeable in the field, and replacing a 16-inch barrel with a 12-inch barrel, reconfiguring the ARX 160 for CQB scenarios, is amazingly simple and fast. Obviously, there will be a POI shift, and the sights have to be re-zeroed, but the POI shift is consistent from change to change and zero settings can be noted down for both barrels.
To remove the barrel, one only need to simultaneously pull down two slide levers located on the sides of the upper receiver in front and above the magazine well. Once freed, the barrel assembly, which includes the gas block, piston system and the barrel extension, can easily be lifted out of the fore-end. The barrel is not free-floated.
The barrel has an integral gas block from which a short telescoping cylinder protrudes. It took a while to fully understand the rather unusual principle of operation: an evolution of the basic gas operated, short stroke piston system.
The engineers at Beretta managed to design a relatively low pressure gas system that is conceptually somewhere in between a long stroke piston system as used in the AK (and the AR 70/90) and the short stroke piston, i.e. of the AR-18 and recent weapons such as the H&K G36 or 416, FN SCAR, Magpul Masada and others. The piston is not limited to fractions of an inch in its travel under the gas pressure drive, imparting a sharp blow to the bolt carrier. Instead, it is free to move for almost two inches, practically following the bolt carrier for most of its rearward travel, and the gas pressure level in the cylinder is relatively low, yielding a gentler and more constant, positive rearward push to the bolt carrier group.
This system allows the barrel to be mechanically free from the bolt carrier group and operating rod, simplifying barrel removal.
The ARX 160’s bolt carrier sports an integral and monolithic milled operating rod, which projects in front of the carrier and also allows some of the weight to be moved forward, helping to tame muzzle lift. Other benefits that this system offers include the chance to position the gas block in the most efficient location. The absence of mechanical constraints between the barrel and the gas system itself prevents any vibration and interference affecting the weapon’s accuracy, a trait of the majority of long stroke firearms with piston and op rod permanently joined to the bolt carrier, such as the AK. It also solves the problem of carbon build up and hot gases entering the action, so typical of AR weapons employing Stoner’s “direct gas impingement” system.
The gas block features a front sling swivel that is free to rotate 180 degrees allowing it to be out of the way when not needed, and a standard M7 bayonet lug, unorthodoxly positioned over, and on top of, the barrel.
The breech end of the barrel features a multi-lugged barrel extension, similar to the one used in the AR-15 family of weapons and of direct descent from Johnson’s system as used in his Model 1941 rifle. The barrel extension solves any headspace related problem and, being the only other part other than barrel, bolt and gas system subject to propellant gas pressure, allows the use of light materials such as polymers for the receiver of the weapon.
The bolt uses seven locking lugs, each radially placed at 40 degrees and two extractors are located respectively at 3 and 9 o’clock of the bolt face. Apparently, there is no ejector. Each extractor is spring loaded and has a small actuating rod that rides within, and extends beyond the rear of the bolt. Depending on how we move a steel block, accessed thru a hole in the rear of the receiver with the tip of a cartridge, an ejection side is selected. The receiver has an ejection port open on both sides and very shallow case deflectors are present just behind each ejection port. They work surprisingly well and the spent round is ejected towards the front with a 45 degree angle from the barrel.
When the bolt unlocks, and starts moving toward the back, the spent case rim is captured by both extractors. Approaching the end of the bolt’s travel, one of the two actuating rods of the extractor assembly hits the steel block and stops, while the bolt and the other extractor assembly keep moving rearwards. The case is violently pushed by the extractor that suddenly stopped, and that now acts as an ejector. The thrust is exerted not on the base of the cartridge but inside the extractor groove, on the chamfered portion of the groove, to be precise.
The bolt itself is a rather complex block of CNC machined forged steel. The body of the bolt is deeply fluted. The grooves serve as cam guides to rotate the bolt, thru an integral pin within the bolt carrier, to actuate locking and unlocking and also to prevent carbon and other grime build up. The firing pin is spring loaded. The bolt rear presents a milled slot where the firing pin head is located. If the bolt is not fully locked, and this slot is not perfectly vertical and aligned with the hammer, the latter cannot reach the firing pin head and even partial out-of-battery firing is totally prevented.
The bolt carrier is quite interesting as well. It is very long and the flat, strip shaped, front portion acts as an operating rod and receives the impulse from the gas cylinder. The upper portion of the carrier presents a milled channel that contains the recoil spring and guide, while the rear portion interfaces with the bolt. The vertical sides of the bolt carrier are flat and smooth. When the bolt is locked, the carrier seals both ejection ports – meaning a port cover is not needed. Between the bolt and the bolt carrier, right behind the bolt head, we find the hinged, small cocking handle and its flat spring. The cocking handle can be positioned indifferently to the left or to the right side of the weapon, depending on the operator’s choice.
The weapon’s body is entirely made of an impact resistant Technopolymer plastic charged with composite fibers, and can be divided in two main assemblies. The upper receiver contains the bolt carrier group, barrel and gas system, and includes the integral handguard and ends with a folding, and partially collapsible, stock. The smaller lower receiver houses the trigger pack, the magazine well and pistol grip. The upper and lower receivers very cleverly interlock with each other when assembled together, and there is no need for receiver push-pins.
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