Gun Review: Faxon Arms ARAK-21

    In 2012, Bob Faxon of Faxon Firearms set out to make an Ar-15 upper receiver that took the best elements of the Ar-15 platform and blended it with the proven Ak-47/AKM/Ak-74/Ak-100 series of weapons. With decades of experience in the automotive, oil, energy, defense, medical and aerospace industries with Faxon Machining, and assistance from a dedicated team of engineers, Bob created a unique upper receiver that is modular, ambidextrous and, due to an adjustable gas regulator, able to handle not only a wide assortment of ammunition brands, but also automatic, suppressed, un-suppressed, supersonic, and subsonic modes of fire. Like the Kalashnikov action, the robust mechanical design and beefed-up bolt allow the ARAK platform to handle calibers other than 5.56×45/.223 Remington, such as 300 AAC Blackout, 7.62×39, and 7.62×51/.308 Winchester.


    FAXON Arms ARAK-21. Bushnell HDMR riflescope.


    The ARAK-21 will work with any Mil-Spec size lower receiver group.

    Key Features of the ARAK-21 I was provided for testing include:

    • Long Stroke variable setting gas piston system
    • 6061-T6 aluminum upper receiver. Upper receiver features a full length Mil-STD-1913 Picatinny top rail as well as three addition rails at the 3, 6, and 9 o’clock positions.
    • The ARAK-21 upper receiver allows a user to quickly change barrels to fit the end user’s specific needs.
    • Ambidextrous, non-reciprocating, folding charging handle.
    • Eight lug, involute profile bolt. The bolt is made of nitrocarburized case hardened 4140 steel. (Rockwell hardness 60) The extractor on the bolt is positioned at the 3 o’clock position. FAXON will be offering an upper receiver that allows for left or right side ejection. The end user will simply remove the cam pin, rotate the bolt 180 degrees, and re-install the cam pin for left side ejection.
    • “Self-contained” firing pin retention system that does not require a cotter pin.
    • The ARAK-21 barrels feature “M4 style” feed ramps.
    • For testing I was initially provided 2 barrels. One 16 inch, 1/7 twist, barrel chambered in 5.56/.223 and one chambered in .300 AAC Blackout (7.62x35mm, 1/8 twist). Those barrels were composed of re-sulpherized 4150 CMV pre-heated steel and were button rifled. The barrels were nitrided using the quench/polish/quench method. FAXON makes all of their barrels in house.
    • During the latter part of testing I was provided a barrel that was composed of 416-R stainless steel. The barrel was 16 inches and fluted.
    • The 5.56 caliber barrels feature a ½ – 28 UNF thread at the muzzle.
    • The 300 AAC Blackout barrel features a 5/8 – 24 UNF thread at the muzzle.

    Testing and Accuracy Round 1

    Initial test fire of the ARAK-21 took place on some BLM land near my home several hours before sunset. The main purpose of that initial test fire was to test magazines and various ammunition types, and to familiarize myself with basic operation and malfunction drills. Ammunition tested was 55 grain Wolf, 55 grain Tula, Federal XM193, Hornady 75 grain .223 MATCH, Federal Premium 77 grain Gold Metal Match, and some 55 grain PMC X-TAC. 300 AAC Blackout was also tested. Please note that only 40 rounds of 300 AAC Blackout 125 grain Remington Premier Match were fired during testing. Magazines used for testing were Troy Battlemags, Generation 1 and Generations 3 Magpul PMAG’s, a 20 round Generation 1 Magpul PMAG, a Thermold 20 round magazine, several US GI magazines that were equipped with anti-tilt followers including the latest tan follower and 1 US GI magazine that was not equipped with an anti-tilt follower.


    Setting up the ARAK-21 for testing. B5 SOPMOD stock. Bushnell TRS-25 red dot sight, Haley Strategic Thorntail Mount and INFORCE WML.

    For testing I made several simple modifications to the ARAK-21. I replaced the factory stock with a B5 Systems SOPMOD stock and, using the Haley Strategic Thorntail offset mount, added the INFORCE WML white/infrared light in the 11 o’clock position. Initially the non-reciprocating charging handle of the ARAK-21 was on the right side, prior to testing the charging handle was moved to the left side. Since I tested an early model, I was not able to attach a Magpul B.A.D lever. Please note that newer models of the ARAK-21 can accommodate the Magpul B.A.D lever. After setting up the charging handle on the left side and blasting through several magazines worth of ammunition, I found that the manual of arms and process for clearing simulated malfunctions was identical to that of the Mk-17/Mk-16/FN-SCAR series of weapons. (Travis Haley has an excellent video on how to run the Mk-17/Mk-16/FN-SCAR.)


    Note the non-reciprocating charging handle. For testing I left the charging handle folded out. It did not interfere with weapons manipulation. I found it comforting to know that I could access it quickly if necessary.

    One feature that is really nice is the fact that the ARAK-21 does not have a reciprocating charging handle. Though the handle folds in and out, for firing I left the charging handle folded out and did not find that it inhibited my weapons manipulation or snagged on clothing or barriers during testing. Please note that the charging handle cannot be used as a forward assist. During testing I had several issues where the bolt did not go completely into battery (This was caused by the gas regulator not allowing enough gas to interface with the piston rod. Easily mitigated by adjusting the regulator to a higher setting). I attempted to close the bolt using the charging handle and inadvertently dislocated it from the receiver assembly. After ejecting the magazine out of the gun and separating the upper and lower receiver of the ARAK-21 for safety reasons, I re-attached the charging handle, re-assembled the firearm, and continued to test the rifle. Subsequent failures to go into battery or failures to eject were solved by adjusting the regulator to allow more gas into the system. This usually happened when switching brands of cheap 5.56/.223. Typically when a failure to feed or failure to eject is experienced an end user should strip the magazine, cycle the gun several time to clear any jams, adjust the gas regulator to the next highest position, re-insert the magazine, cycle the action, and continue firing.


    ARAK-21 gas adjuster. This feature lends a lot of flexibility to the platform. Note the hole on the gas adjuster. Should the gas adjuster get hot or dirty, a spent casing can be used to turn the adjuster.

    As previously mentioned, the ARAK-21 has is an adjustable gas regulator. The gas regulator sits atop the gas block and has 5 positions. 5.56/.223 ammunition brands produce slightly different pressures, which became apparent during testing. Some brands of ammunition produced a lower pressure when fired, and the gas port had to be adjusted to allow more gas to interface with the piston. A typical sign that the system is not getting enough gas is a failure to eject or a failure of the bolt to go fully into battery. Simply turn the gas regulator to a high setting to mitigate these problems. Before taking the ARAK-21 into harm’s way, test your ammunition and determine the optimal setting. This is an absolute must with 300 AAC Backout.

    The gas regulator on the ARAK-21 has 5 positions/settings.

    Position 1 allows the end user to remove the gas regulator for cleaning. Even though the ARAK-21 has a long stroke piston, carbon will accumulate around the gas regulator. Please note that when the ARAK-21 gets dirty, the regulator will be difficult to turn. FAXON cut a hole in which the end user can use a shell casing to rotate the regulator.

    Position 2 is a low gas setting. Use this setting when running Mil Spec ammunition. The 55 grain Federal XM-193 and the 55 grain PMC X-TAC ran fine at this setting. WOLF, TULA, Hornady .223 MATCH and Federal Premium .223 did not run very well at this setting and failures to feed/extract were experienced. If running suppressed, Position 2 would be my starting point, given that the suppressor will trap gasses.

    Position 3 is a Medium gas setting. WOLF, TULA, Hornady .223 MATCH and Federal Premium ran well at this setting, as did 300 AAC Blackout 125 grain Remington Premium Match.

    Position 4 is a Maximum gas setting. I ran several rounds through the ARAK-21 at this setting. When firing the Federal XM-193 the gun cycled really fast. I did not observe any bolt bounce or feed issues at this setting. I would not run suppressed at this setting for fear that the amount of energy being transferred to the operating rod and bolt carrier would damage the hammer, disconnector, trigger pins or hammer pins. I would also be concerned whether a magazine could match the high cyclic rate of the rifle, should the ARAK-21 be fired in fully automatic at this setting.

    Position 5 does not allow gas to interface with the piston. Position 5 turns the ARAK-21 into a single shot firearm, where an end user would have to manually cycle the bolt to eject a round, reset the hammer, and pick up another round from the magazine. I might use this setting if I was using the ARAK-21 to introduce a young shooter to firearms.


    Accuracy Testing Round 2.

    The first round of accuracy testing of the ARAK-21 was done at the family ranch. All shooting was done in the prone position with a heavy load on the bipod. Prior to testing, the barrel was cleaned of carbon and copper. For testing I used a Generation 1 20 round Magpul Pmag and a Bushnell HDMR 3.5-21 First Focal Place rifle scope. My Bushnell HDMR is equipped with the awesome Horus H59 reticle and mounts with a quick detach LaRue Tactical mount. After getting “on paper” at 25 yards, I moved the target back to 100 yards, topped off the 20 round Pmag with Federal XM-193, proned out, found natural point of aim, and started testing. I fired a 3 round group at 100 yards. The initial group was about 6 inches high in regards to point of aim. I made several adjustments to the elevation knob and gave the barrel a few minutes to cool. When the barrel was cool to the touch, I fired 5 additional rounds. The shots all went a little bit lower, as expected, but I could not shoot better than a 4 inch group. After letting the barrel cool, and taking into account the barrel I was shooting had a 1/7 twist, I switched over to 75 grain Hornady Match grade ammunition and fired another 5 round group. My group once again hovered in the area of 4 inches. Frustrated that I might be the reason for the horrible results I grabbed my personal Ar-15 and proceeded to fire a 5 shot group at 100 yards. Walking down to the target and using a set of calipers, my group, shot with Federal XM-193, measured 1.4 inches. After trying several other types of ammunition through the ARAK-21 and getting similar results, I decided to swap out the barrel to 300 AAC blackout and try my luck with the .30 caliber. After swapping out the Barreled Upper Units, I settled in and started testing. To my surprise, my first 2 shots were about an inch apart. After slowly squeezing the trigger 3 more times I was pleased to see all of my shots within a rough 1.5 inch group.

    FAXON arms was contacted about the terrible accuracy of the 5.56/.223 barrel. The representative stated that they had made a bad batch of barrels, and that a new barrel was headed to me for testing. The previous barrels that I had tested were a thinner profile. The barrel that arrived several days later, was a medium profile, stainless steel barrel (416-R) with a 1/8 twist rate.


    In order to swap a barrel a end user will have to remove the receiver forearm.


    Removing the receiver forearm will require a 5/32 allen driver. After swapping the barrel, the Allen screws are torqued on at 30 in/LBS. Do not over tighten.


    Upper receiver, Barreled Upper Unit and receiver forearm. Note the heavy trunion on the barrel and the rails that interface with the upper receiver.

    After installing the new barrel I headed back out to the ranch. From the pictures below you can see the results of the new barrel. All groups were shot at 100 yards in the prone position from a loaded bipod. 5 shots were fired from each type of ammunition. The barrel was not allowed to cool between groups. The accuracy capability of the ARAK-21 is simply astounding.


    The replacement barrel that FAXON sent me was match grade accurate. All groups were fired prone at 100 yards. For testing I shot 5 shot groups, and did not allow the barrel to cool between shots. Group 1 – Hornady 223 Remington. 75 grain BTHP. (.687 inch group) Group 2 – Federal Premium Gold Medal Match. 77 grain Sierra Matchking BTHP. (.616 inch group) Group 3 – Federal XM-193 55 grain BT. (1.038 inch group) Group 4 – Tulammo. 55 grain FMJ (1.185 inch group)


    Maintenance schedules and cleaning.

    After firing several hundred rounds through the ARAK-21 over the course of several months, it was time to get it back to FAXON arms. Before sending it back the gun was disassembled and cleaned. The operating rod, gas cylinder, gas regulator, bore, and bolt face experienced carbon build up. There was a lot of carbon in the bore, probably due to the cheap steel ammunition fired during testing. For cleaning I doused all the parts that had carbon with MPRO-7, ran a wet patch down the barrel, and went and made a cup of coffee. After about 10 minutes, I returned and with the help of a brass brush and some RamRodz, cleaned all the carbon from the gun. Several passes with a cleaning rod and some patches finalized the cleaning job and the rifle was packed up for shipping. Cleaning time was about the same as an Ar-15. Had I been shooting the ARAK-21 suppressed, cleaning time would have been a lot longer.

    Maintenance Schedule as recommended by the Manufacturer:

    • Replace Extractor Spring every 5000 rounds.
    • Replace Ejector Springs every 5000 rounds.
    • Replace Extractor every 5000 rounds.
    • Replace the Main Recoil Spring every 10,000 rounds.

    Recoil spring guide retainer pin. After separating the upper and lower receiver this is the first step to disassembling the upper receiver.


    Disassembled upper receiver ready for cleaning. Note the carbon on the operating rod.



    The bolt carrier group disassembled. Note the lack of cotter pin.


    Top – Arak-21 bolt. Bottom – Ar-15/M16 Bolt. Note the lack of gas rings on the Arak-21 bolt and the “beefed” up design.


    Left – Standard Ar-15/M16 bolt. Right – Arak-21 bolt. Note the size, dual ejectors and the 8 involute profile lugs. Faxon makes their bolts out of case hardened 4140 steel.

    Observations and Opinion

    • It is not a secret that FAXON produced some bad barrels. If you are not satisfied with the accuracy of your ARAK-21 call FAXON and they will address the issue.
    • A forward assist would be a nice feature on the ARAK-21.
    • After tuning the ammunition to the appropriate regulator position the ARAK-21 performed well. All malfunctions were due to not having enough gas interface with the piston. The ARAK-21 fed from all magazines used during testing.
    • Testing ammunition and tuning the gas regulator is an absolute must if you are going to take the ARAK-21 into harm’s way.
    • It would be nice if the handguard on the ARAK-21 was a little bit longer. M-LOK and KeyMod feature would also be nice.
    • The Black Loud Mouth muzzle brake that came with the ARAK-21 was very effective at mitigating recoil and muzzle rise, and at blooming out my night vision monocle. I have no need for muzzle brakes on my carbines, but if I were doing a competition, the Black Loud Mouth brake would be an awesome accessory. The Black Loud Mouth brake did come loose during testing. Since there is no way to tighten it with tools this was continually a problem. If I were running an ARAK-21 I would ditch the muzzle brake and install a simple A2 flash hider and a crush washer.
    • The model I tested could not accommodate a Magpul B.A.D lever. Newer models of the ARAK-21 will work with the Magpul B.A.D lever.
    • The ARAK-21 mated well to several Mil-Spec sized lower receivers. It also worked fine with a “billet” lower receiver from Billet Rifle Systems.
    • If I were running the ARAK-21 suppressed I would invest in an ultrasonic cleaner. Because the weapon system easily breaks down, you can get most of the parts in an ultrasonic bath.
    • Be mindful of your gas regulator when shooting at night. I was running a course of fire when I switched over to some crappy underpowered Tula ammunition. Immediately the gun started to short stroke. I accidentally rotated the gas regulator to Position 1 as opposed to Position 3. Position 1 allows an end user to remove the gas regulator. Coming back on target I fired the next round and watched as the gas adjuster launched away from the gun, never to be found again.
    • I would keep a spare charging handle, gas adjuster, extractor, and extractor spring in the pistol grip or stock compartment. During testing I accidentally pulled off the charging handle, and I was able to loose the gas adjuster by not paying attention (On my personal Ar-15 I keep spare gas rings, extractor, extractor spring, bolt, CRANE o-ring, firing pin, surefire CR123 batteries, and surefire ear protection in my BCM gunfighter grip and B5 SOPMOD stock).
    • The Arak-21 I tested was capable of Match grade accuracy. Faxon makes Ar-15 barrels.

    Final Thoughts

    I was skeptical of the ARAK-21 when it first came out. Erroneously I chalked it up as nothing more than another Ar-18 clone. After coming across it again in Issue 6 of RECOIL magazine, I realized it wasn’t an Ar-18 but a true hybrid of the Kalashnikov and Ar-15/M16 platforms. Should you purchase an ARAK-21? If you run a 5.56/.223 Ar-15 with either a 14.5 carbine length gas system or a 16 inch mid-length gas system, quality Mil-spec ammunition, un-suppressed, you probably don’t need an ARAK-21 since those systems are extremely reliable. If you want the option to quickly swap out barrels, the ARAK-21 is for you. If you want the ability to run a lot of different brands of ammunition, the ARAK-21 is for you. If you run short barreled rifles, suppressed and un-suppressed, the ARAK-21 is for you. If you shoot at very high elevations, the ARAK-21 is for you. If you like to shoot 300 AAC Blackout, suppressed and un-suppressed, the ARAK-21 is for you. If you shoot a lot of fully automatic fire, the ARAK-21 is for you. If you like to collect cool guns…the ARAK-21 is for you. Over the last several months I got to fire several hundred rounds through the ARAK-21. When the ammunition was paired with the appropriate gas setting, the ARAK-21 was extremely reliable. Like its predecessors, the AR-15 and the AK-47, I think the ARAK-21 is going to be with us a long time. I look forward to the evolution of this platform. If only Mikhail Kalashnikov and Eugene Stoner were still alive to get a few hours on the range with this weapon system…that would truly be a site to behold.

    For those of you going to SHOT… and those not going to SHOT. Faxon recently announced the ARAK-31, which they will be releasing at SHOT! The ARAK -31 will be chambered in 7.62×51/.308 Winchester. Aside from the ARAK-31, Faxon will be showcasing the 7.62×39 Barreled Upper Receiver, a reverse compatible longer handguard as well as a receiver for the ARAK-21 that will allow left or right side ejection. Faxon Arms will be at booth #7006.

    Thoughts, comments, gripes, and humor are welcome in the comments below.

    Vive La France

    Vive la France. Vive la liberte… 

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    Thomas Gomez

    Thomas Gomez currently resides in the mountains of central New Mexico. He has an M.B.A, an Ar-15/M16/M4 armorer certification from Specialized Armament Warehouse as well as a Glock armorer certification. Aside from writing for The Firearm Blog he works as a Clinical Analyst for a large Hospital. He spends his free time farming, ranching, hiking, fly-fishing and hunting in the beautiful forests and prairies of New Mexico. He can be reached at [email protected]