ARAK-21: AK or AR

By Chris A. Choat

The SHOT Show is THE showplace for all things new in the firearms world and in January of this 2013 a new item was being introduced that definitely looked like it was going to be of interest to anyone that appreciates the AR platform of rifles. At SHOT Show 2014 it will be fully on display, and is a mature product in the marketplace. The new product was a complete barreled upper receiver unit made to fit any standard AR-15 series lower receiver which, while not earth-shattering news, the unit had several innovative features that seemed it would place it at the head of the pack. The new unit was called the ARAK-21 and would be produced by a company called Faxon Firearms.

In talking to the representatives at Faxon Firearms at the show, plans were made to do an article on this new unit as soon as production units were available. Small Arms Review does not do test and evaluations on a pre-production “prepped” unit. We want the same out-of-the-box production gun that anyone else would get. Several months went by and a box arrived with the new unit.

Innovative Features

One of the first things noticed was that the entire upper receiver and forearm was monolithic and machined from a solid billet of 6061 T-6 aluminum. The next feature that was very evident was that the unit was a piston driven unit. While this may not seem noteworthy at first, but the entire recoil system was also contained in the upper much like the AK series. There was no need for a lower receiver mounted buffer and recoil spring. This was big news because it now allows for the host rifle to be equipped with a folding stock. But the new innovations didn’t stop there. The ARAK-21 also featured a relatively quick-change barrel system which meant that it could be changed easily from its original .223/5.56 caliber to other calibers as well as different barrel lengths. If these innovations weren’t enough, the unit also incorporates a forward mounted, non-reciprocating charging handle that can be switched to either the right or left hand side of the gun.

The unit received for testing came with the complete ARAK-21 upper with .223/5.56 16-inch barrel installed as well as another 16-inch barrel in 300 Blackout. Barrels are available in 16- and 20-inch versions and just as this article is going to press a 12.5-inch barrel is being introduced for use on short barrel rifles. A billet upper such as this just begs to be installed on a billet lower and as luck would have it I had just received a new billet lower receiver made by S.W.A.T. Firearms of Campbell, Texas. These receivers are machined from a solid billet of aluminum and feature an enlarged trigger guard as well as a funneled magazine well. They are also available in a variety of different colors. The only other thing that was needed was a folding stock to show off the ARAK-21’s internal recoil system. An Arizona company, AGP Arms, is now producing a side folding stock that will fit an AR series lower. Though it was originally produced to fit .22 caliber AR style guns, it fits and functions fine on larger caliber guns as well. The new stock is made from polymer and features a push button release that allows it to fold to the right side of the gun. It also has sockets for QD push button sling swivels and has optional rubber buttpads in several thicknesses to fit any shooter. It comes complete with all mounting hardware. A call to AGP and a stock was on its way.

The ARAK-21 has a Mil-Spec 15-inch Picatinny rail that runs along the top of the upper. The forearm also has 6.5-inch bolt-on rails at the 3 and 9 o’clock positions. The bottom of the forearm also has a 6.5-inch rail bolted to it. This bottom forearm piece is held on by 6 Allen head machine screws. Loosening these screws and removing the forearm bottom piece are all that is needed to change barrels.

The ARAK-21 uses a long stroke piston operating system. It features a five position adjustable gas regulator that can be tailored for any style ammunition as well as suppressor use. This regulator can be adjusted without the need for tools either by hand or, if hot, with the tip of a cartridge. This type of system keeps the rifle extremely clean and does not introduce an excessive amount of heat into the gun. It also produces very low felt recoil. The unit has a two-stage recoil spring that remains captive in the upper receiver when it is removed from the lower. The upper will fit any AR-15/M16 Mil-Spec lower with no modifications; just pull the two takedown pins, remove the existing upper and drop on the ARAK unit. The new unit uses a proprietary bolt system that features eight lugs and has a parabolic profile, which is said to be 30% stronger that standard AR bolts. The bolt rides on hardened steel rails bolted into the upper receiver. It has a self-contained firing pin retention system that doesn’t use a separate cotter pin to hold the firing pin in the carrier. It is also capable of being used either right or left handed. That being said, there is both a right and left handed version of the ARAK-21 and an ambidextrous unit will be available in the near future.

The gun was first tested in 300 Blackout as .223 ammunition was non-existent in my locale. The unit comes with two recoil springs, one for .223/5.56 and the other for use with the 300 Blackout barrel. The springs are color coded with the .223/5.56 spring being black while the 300 Blackout spring is yellow. The yellow spring is also 2.5 inches shorter than the black spring. The owners manual states that while you may be able to shoot 300 Blackout with the .223/5.56 spring installed, the reverse is not true. If you are shooting .223 or 5.56 ammunition you MUST use the black .223/5.56 spring because of the higher pressures. The recoil spring is actually 2 springs held together by what is called a recoil spring connector. This 2-spring assembly gives the unit a two-stage recoil system that works very well.

As the unit was sent with the .223/5.56 barrel and recoil spring installed, the first business of order was to change it over to 300 Blackout. The upper receiver needs to be off of the lower to change the barrel and the bolt needs to be taken out of the upper. Once the upper and lower are separated, the only tool needed is a 5/32 inch Allen wrench, which is sent with the upper. You loosen 6 screws that hold the bottom portion of the railed forearm in place and remove this piece. The screws are held captive so there are no loose pieces to worry about losing. This is a nice touch and an absolute must for any serious weapon system. Once the bottom piece is removed from the forearm the barrel can be slid forward out of the upper receiver. The new barrel is slid into place and the 6 screws are tightened down. It is that easy and can be done in less than 3 minutes. You are cautioned in the manual to not over tighten the screws. It is recommended to torque them to 30 in/lbs but this author did fine by just hand tightening them. They never worked loose in all of my testing. You then replace the bolt, substitute the appropriate recoil spring, put the upper back on the lower and you are ready to fire.

The .223/5.56 barrel has a 1 in 7 twist and the 300 Blackout has a 1 in 8. The barrels are threaded and come complete with Faxon’s own flash hiders that are engraved on the muzzle end as to which caliber they are. The .223/5.56 barrels are threaded 1/2x28 and the 300 Blackout barrels are threaded 5/8x24, which is the industry standard. Barrels are available in either a medium or heavy weight profile. The barrels in the test kit came with the .223 in a medium weight and the 300 blackout in a heavy. The barrels are made in-house by Faxon and are gun drilled, gun reamed and button rifled. The entire barrel assembly is black nitrided to match the upper. Each barrel is also engraved with its caliber designation.


Testing was done at the standard 100 yards in two sessions: first with the 300 Blackout and then the second session was done a few weeks later when some .223 ammunition could be obtained. The gun was equipped with a Nightforce NXS 2.5-10x24, 30 mm scope. The reticle in this scope was their circle with a center dot type that proves to be good for CQB ranges as well as anything out to 200 yards. The 300 Blackout ammunition that was used was Remington and included both 115 grain FMJ-BT supersonic as well as 220 grain OTM subsonic. Five shot groups were fired from a table with a Harris bipod attached to the gun’s forearm and a rear sandbag rest. 50 rounds of the 115 grain supersonic were fired first and not one group measured over 1.5 inches. 50 rounds of the 220 grain subsonic was then fired, also in 5-shot groups, with the group sized opening up to just under 2 inches. The barrel was then removed, then reinstalled and the same test repeated. Again the groups were consistent with the first shots fired and the point of impact for each load stayed the same. In other words you can remove the barrel and reinstall it with absolutely no change of zero. The same tests were repeated a few weeks later when some .223 ammunition was sourced with the same, if not better, results. The .223 groups actually shrank by about 1/4 inch. Some Hornady 75 grain BTHP Match ammunition was used that produced groups of 1/2 MOA. This upper really produced some amazing accuracy.

The reliability of the upper was perfect. It digested every type of ammunition that was put into it from the very first round. The only hiccup that occurred was when the gun was inadvertently fired using the 300 Blackout barrel with the .223 recoil spring installed. The gun fired and ejected the empty but the bolt was not blown back far enough to pick up the next round. It was without doubt my fault for installing the wrong recoil spring and was no fault of the upper itself.

The machining tolerances on the ARAK-21 are very close as was seen by the group size and the repeatability when the barrel was removed and reinstalled. The unit is a good looking, rugged and extremely reliable. Right now the unit comes in .223/5.56 and 300 Blackout, which are the logical choices and is great as you can use the same bolt and magazine for either caliber. Faxon Firearms has informed SAR that other calibers are on the horizon with possibly 6.5 Grendel being one of the first. The ARAK-21 combines the best advantages of both the AR and the AK series of guns with the latest and greatest machining and production techniques. The quick change barrel and the ability to add a folding stock to the AR platform are just icing on an extremely great cake.

Faxon Firearms
11101 Adwood Drive
Cincinnati, OH 45240
Phone: (513) 674-2580
Website: www.faxonfirearms.com

AGP Arms Inc.
1930 E. 3rd Street, Suite #12
Tempe, AZ 85281
Phone: (480) 983-6083
Website: www.agparms.com

S.W.A.T. Firearms
6585 East I-30
Campbell, TX 75422
Phone: (903) 862-2408
Website: www.swatfirearms.com

This article first appeared in Small Arms Review V18N1 (February 2014)
and was posted online on November 15, 2013


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