It is nice to see a product evolve over time. The ArmaLite AR-31 .308 Win rifle is a great case in point. The AR-31 shares its design lineage with previous ArmaLite precision rifles in the form of the AR-30 and its updated version AR-30A1. The AR-30A1 rifle is chambered in “long action” bolt cartridges such as .300 WinMag and .338 Lapua. The AR-31 takes the no nonsense ArmaLite concept of the tactical rifle another step forward. While the AR-31 (and AR-30A1) may resemble its AR-30 predecessor, only the pistol grip, buttpad, trigger, and a few small components from the original AR-30 transferred over to the AR-31. All other components are new or redesigned. This is especially true with the AR-31’s bolt action. The AR-31’s “short action” describes the length the bolt needs to travel to function/cycle the .308Win cartridge. The longer .300 WinMag and .338 Lapua cartridges require a “long action.” The AR-31’s shorter action provides for a stiffer receiver often translating into better accuracy.

The AR-31 aluminum stock is better described as a “chassis.” The aluminum stock reinforces the receiver like a sleeved bench rest rifle. ArmaLite equips the AR-31 with a competition grade barrel and patented V-block receiver bedding system. These two components are key components to the AR-31’s sub-minute of angle accuracy expectations. There is no bedding in a traditional sense involved with the AR-31; instead a mechanical metal to metal fit is utilized literally wedging the receiver to the stock. ArmaLite’s V-bloc mates the stock to the receiver assuring stability and repeatable accuracy. The ArmaLite aluminum chassis, while not as svelte as a classic wood stock or even fiberglass stock, is very functional for a rifle destined for tactical use. All of the AR-31’s features are calculated to enhance the user’s ability to surgically place .308 Win rounds on target at distance.

ArmaLite’s decision to incorporate detachable high capacity AR-10B magazines into the AR-31 sets it apart from most other precision rifles on the market.

Other than its .308Win chambering, one major difference between the AR-31 and AR-30A1 series is being configured with a magazine well to accommodate AR-10B detachable magazines. The AR-10B magazines come in 5-, 10-, 15-, 20- and 25-round capacities. The AR-31 is not a compact rifle. It features a 24-inch, 1:10 twist barrel contributing to an overall length of nearly 46 inches. The rifle weighs 13 pounds empty. The trigger is a single stage affair measuring 4 pounds of pull weight. The stock is fixed with a 13.5 inch length of pull. ArmaLite literature states 1/4-3/4 MOA accuracy is to be expected with the AR-31. The AR-31 is finished with military grade anodizing and phosphating coating to enhance durability and corrosion resistance. The rail atop the receiver for mounting scopes includes 20 minute angled allowing for extended range zeroing.

A unique aesthetic with the AR-31 is the proven ArmaLite muzzle brake screwed on via 5/8 x 24 thread pitch. The threaded muzzle brake on the AR-31 is a standalone feature in its own right. The ArmaLite muzzle brake design was proofed on their AR-50 .50 BMG and is just as effective on the AR-31 allowing for a full range day of firing with no ill effect on shooter in terms of recoil. With that said, if needed, the factory threaded muzzle brake is quickly removed and allows for the AR-31 to be easily adapted for use with a suppressor.

Left to right are .308Win, 300WinMag & .338 Lapua cartridges. The .308Win is an established tactical chambering, especially for law enforcement, with the .300WinMag & .338 Lapua considered more specialized 1,000+ yard long range cartridges.

For this evaluation a Schmidt & Bender 5-25x56mm PM II with H2 CMR reticle was mounted on the AR-31 via AWP rings. In the past few years, Schmidt & Bender (S&B) has made a couple of powerful statements by winning two of the most prestigious U.S. military optic contracts. Most recently, S&B was chosen to provide the optic for the U.S. Precision Sniper Rifle (PSR). Schmidt & Bender will be supplying its 5-25×56 PMII scope in a special PSR version to U.S. Army, Navy, Air Force and Marine Special Forces for existing and future sniper rifles. The Schmidt & Bender optic is expected to serve and perform all over the world under widely varying and harsh environmental conditions; whether under water, near coastlines, in arctic surroundings, in the jungle or desert and last, but not least, in urban warfare. Another milestone that established Schmidt & Bender as a major player in the tactical optic market was the S&B 3-12×50 PM II model being chosen for use by the U.S. Marines on their sniper rifles. This was after two years of comprehensive testing by the U.S. Marines against 25 rival scopes.

An American Technologies Network Corporation (ATN) PS22 NVD was used when testing the AR-31 in a night time role. The PS22 is designed to mount in front of a day optic scope. That sounds pretty simple and self-explanatory. However, this feature blows away previous attempts to adapt a day optic scope for use at night. The entire concept is based on wanting to give the user the convenience of using their day optic at night without having to switch out aiming devices or having to dedicate a weapon solely for use at night. Any weapon can be adapted for night use as long as the ATN PS22 can be placed in front of a suitable day optic device. The available choices for the day optic that are compatible to use with the PS22 is wide ranging. One important advantage of the PS22 concept is not requiring the optic to be sighted in every time it is employed, since the day optic never moves. The PS2 is attached or detached with no impact on the day optic’s point of aim and parallax is not an issue. Another benefit of the PS22 is that a scope’s reticle does not need to be illuminated or IR compatible for it to be visible when using the PS22. The extended ArmaLite rail system is ideal for mounting the ATN PS22. The visual quality of the PS22 must be experienced to be fully appreciated with precise fire possible out to 200 yards or further depending on ambient light night conditions. The ATN PS22 serves as force multiplier when employed on the ArmaLite AR-31 allowing for 24 hour use.

The AR-31’s safety is a toggle type leaving operator no doubt what state their rifle is in either in daylight or night time use.

The ArmaLite AR-31 was tested over an extended time period constantly producing sub-MOA groups with several different ammunition brands – an important logistic consideration. Various .308Win loadings from Black Hills Ammunition, Federal, Winchester, and Hornady provided the basis for the accuracy tests. The Black Hills Match loads tested consisted of 168 grain and 175 grain Match bullets. The Federal chambering was the venerable 168 grain Match load. 168 grain TAP from Hornady along with Winchester 168 grain Match was also used. The AR-31’s 24-inch barrel produced velocity as promised with the 168 grain and 175 grain loads clocking in at the low to mid 2,600 fps range. As to be expected with quality ammunition, velocity figures within the different loads deviated very little from round to round. This is critical for predicable long range accuracy.

The ArmaLite rifle shot all the premium loads tested into 1 MOA or better at 100 yards; mostly better with 5/8” groups not untypical. It was not deemed necessary to cast the net wider, since Black Hills Ammunition, Federal, Winchester, and Hornady are industry leaders, which is what this type of rifle deserves to wring out its full potential. The bench testing was done off a Champion tripod front rest and rear sand bag. The accuracy figures are based on firing three five-round groups and averaging group sizes. While not statistically full proof, the method certainly represents the AR-31’s capabilities. The Federal 168 grain Match and BHA 175 grain Match produced the best 100 yard accuracy average at only slightly above 1/2”. Rifles can exhibit finicky behavior over which loads are preferred. Again, no loads were over 1 MOA. Another sign of an accurate, dependable rifle is how cold bore zeros compare over time and if the point of aim shifts after a few rounds heat up the barrel. The AR-31 showed no shifts in point of aim and cold bore zeros produced fine groups when overlaid together.

The rear buttstock of the AR-31 is adjustable for optimum cheek weld & length of pull for individual users.

Not a lot of time was spent at the 100 yard range. 300 yards and out is the more indicative test of a weapon system like the ArmaLite AR-31. This generates useful ballistic information for the shooter, especially when it comes to elevation and windage data for log books and ballistic calculations. A tactical rifle weapon system is made up of rifle/optics/ammunition/shooter. Groups were fired at 300 yards with the Federal 168 grain Match and BHA 175 grain Match loads performing the best again. Significantly, all of the loads held onto the 1 MOA (approximately 3” at 300 yard) or better criteria. Most shooters cannot take advantage of this kind of performance.

After testing innate accuracy from the bench, field tests were performed at Echo Valley Training Center (EVTC). This consisted of shooting prone off a bipod or pack. A favorite reactive target has always been the clay pigeon. The bolt was worked as quickly as possible with the next target acquired rapidly for engagement. The AR-31’s muzzle device combined with the ergonomic stock and slick bolt with short lift proved potent. Another note of interest was how easy the Schmidt & Bender H2 CMR reticle made hitting targets at 300 yards and beyond; thanks to sharp image clear hold over points if required. The benefit is obvious of holding directly on target versus an estimated hold over. Also, the H2 CMR reticle is a great tool for estimating target range once one is familiar with the method. Other range work consisted of shooting B-27 man-targets out to 500 yards. The AR-31’s accuracy combined with clear powerful Schmidt & Bender optics enabled rote center mass hits. It was even tempting to try head shots at that distance. Another favorite evaluation drill is to shoot at a Mike Gibson Manufacturing (MGM) Precision Rifle Target placed at 300 yard from the prone position. The MGM Precision Rifle Target features movable target doors simulating the small eye/nose and center chest areas that “open” and “shut” when hit. This provides feedback as to how a rifle performs in terms of bolt manipulation and how the stock interacts with the shooter during recoil as compared to firing off the bench at 100 yards. The combination of the world class Schmidt & Bender 5-25x optics and the AR-31 generated great performance. The work-up at EVTC was done in preparation for much longer range work in mind. EVTC has access to various off site locations where up to 1,000 yards is available. This is a rare commodity, especially outside of any military controlled property.

Initial range work supported by Champion bags from the bench to get the AR-31 zeroed in.

It was decided to further test the ArmaLite AR-31 using a competition format discovered at a local LE shoot attended annually. Competitors are tasked with engaging multiple hanging clay pigeons at 220 yards followed up with firing at more clay pigeons at 285 yards and then 1/4 scale steel targets placed at 350 yards. Shooting is from the prone position supported by bipod in the front and bag under the buttstock. The inherit accuracy of the AR-31 combined with higher than normal capacity for a bolt action made short work of the course of fire. The oversize handle and smooth passage of the bolt in the raceway allows for minimal disturbance when the rifle’s bolt is worked allowing for fast follow-up shots when engaging multiple targets. The AR-31 stoutly ejected empty cases. One note of interest with the AR-31 is that single loading a cartridge is not feasible as it with other bolt action. This is due to the bolt locking back on the magazine’s follower. With capacity offered by the AR-10B magazines and ease of switching out magazines providing for a “reload,” the practice of single loading cartridges is not as crucial with the AR-31 as it would be with a typical five round bolt action rifle.

There are many “tactical” rifles on the market that are labeled as such based solely on a heavy barrel in a synthetic stock. This is not the case with the ArmaLite AR-31 chambered in .308Win. ArmaLite does not curry for cross over sales appeal with the AR-31. The rifle is a tactical weapon with all design inputs stemming solely from tactical considerations and needs.

.338 Lapua round laid into ejection port area of AR-31 showing why the AR-31 .308Win is a “short action” bolt.

SITES OF INTEREST

ArmaLite, Inc.
P.O. Box 299
Geneseo, IL. 61254
(800) 336-0184
www.ArmaLite.com

Schmidt & Bender USA, Inc.
Service Center
(703) 953 1253
www.schmidtundbender.de

Echo Valley Training Center
www.echovalleytrainingcenter.com

Winchester Ammunition
427 N. Shamrock St
East Alton, IL 62024
www.winchester.com

Black Hills Ammunition
PO Box 3090
Rapid City, SD 57709
(605) 348-5150
www.black-hills.com

ATK/Federal Cartridge Company
900 Ehlen Drive
Anoka, MN 55303
(8000 322-2342
www.federalpremium.com

Hornady Mfg. Inc.
3625 Old Potash Hwy
Grand Island, NE 68802
(800) 338-3220
www.hornady.com

ArmaLite has configured the .308Win chambered AR-31 in a way that allows individual users to adapt it to a variety of roles.

The AR-15/M16/M4 series rifle is undoubtedly the most popular rifle in the United State for all military, law enforcement and commercial markets.  It is the most versatile platform of a rifle on the face of the planet.  Another rifle has crept up into that popularity; one that was on the scrap heap of the U.S. Army for nearly 40 years.  That would be the one that started it all, the AR-10.  “Tomorrow’s Rifle Today” in the late 1950s has turned out to be today’s rifle today.  The rifle that Ordnance Corp would dismiss in the late 1950s would have its day in the late 1990s and in the new millennium would serve as the primary sniper rifle for the U.S. Special Operations Command as well as the U.S. Army, replacing M24 bolt action rifles.  But where did all this begin?

In 1953, George Sullivan gained interest from Richard Boutelle of Fairchild Engine and Aircraft for his idea of developing a small arms design firm.  Boutelle, a gun enthusiast himself, invested capital to start up this new company on 1 October 1954.  The money came from the research and development budget of Fairchild.  This company would have an impact on the history and direction of the modern battle rifle in the U.S. beyond Sullivan’s and Boutelle’s expectations.  ArmaLite Corporation was born.  The Fairchild winged Pegasus would have a circle and cross hairs superimposed as the symbol of the new corporation.  ArmaLite was envisioned to be a “think tank,” not a small arms manufacturer.  The new designs were to be made but manufactured by a dedicated manufacturing facility.

Much success in life is timing, being in the right place at the right time.  Even more so, having an individual that knows how to spot talent and grab it.  While working on a prototype rifle, George Sullivan was test firing his design at the Topanga Canyon Shooting Range outside of Los Angeles where he saw and met a young man who was doing the exact same thing.  That young man was Eugene Morrison Stoner.

Shown is a Portuguese soldier with is A.I. AR-10. The Portuguese Army was well satisfied with the performance of the AR-10 and would have procured more if A.I. would not have cut off production.

Stoner was born in Gasport, Indiana on November 11, 1922.  His family would later move to California.  In 1939, Stoner worked for Vega Aircraft and with the U.S. entering World War II Stoner would serve in the Marine Corps as an Ordnance Specialist.  At the time of his chance meeting with Sullivan, Stoner was making dental plates and in his spare time he would design advanced rifles.  Sullivan was very impressed with the rifle Stoner was testing, later known as the M5 (it evolved into the AR-3), and hired him as the Chief Design Engineer at ArmaLite.  The AR-3 was granted U.S. Patent Number 2,951,424.

Stoner was a genius; well ahead of his time particularly in the firearms industry at that time.  In fact, radical would be the proper word.  In a world of tradition that required steel and wood, young Stoner would take his experience in the state-of-the-art aircraft industry and apply that technology to firearms development.  Using aircraft grade aluminum and synthetic materials in place of the traditional wood and steel, Stoner would create the lightest battle rifle in the world.  But was the world, particularly the U.S. Ordnance Corps, ready for it?

Stoner’s new concept, the AR-10 would deviate from tradition.  First, the AR-10 would be completely inline in construction.  Meaning the barrel, bolt, bolt carrier and recoil spring and buffer were directly in line with the shooters shoulder.  This reduces traditional muzzle rise and felt recoil compared to the traditional M1/M14 rifles.  This also makes the rifle firing in fully automatic that much more controllable.  Due to no drop in the stock, the sights had to be raised so the shooter could see through them; hence the carrying handle (third prototype) was born which would become an icon for Stoner designed weapons.

The first prototype rifle had the needed raised front and rear sight and was chambered for the 7.62x63mm (30-06 Springfield) cartridge.  The cartridges were fed from a standard BAR magazine.  The stock was a tubular stock with a butt plate added to the rear.  This rifle used the same direct gas system used in Stoners AR-3 rifle which we will discuss in more detail.

Shown is the bolt carrier group of serial number 1004 after firing 409 rounds. This picture is to depict the carbon fouling on the bolt carrier group.

The second prototype added a telescope sight, which was raised up to allow the shooter’s eye to align.  Stoner added a more conventional stock to the rifle.  The pistol grip was made from the same material as the stock and hand guards.  There were no iron sights on this model.  This model also differed in that it was chambered for the 7.62x51mm cartridge that was soon to be adopted as the standard cartridge for the U.S. military.

The third prototype was far more close to the finalized AR-10.  Many new features were added and also the gas system was altered.  The first thing you notice is the carrying handle on the upper receiver containing the rear sight as well as the raised front sight that is attached to a muzzle compensator.  The bolt was designed after the Mel Johnson designed multi lug bolt.  There are seven lugs as well as the extractor.

This rifle used a unique new gas system.  Although previously used on the Swedish AG42B and the French MAS44 and MAS49/56, the new part of the system was to be a gas cut off once enough gas was used to operate the action.  This reduced recoil as well as increased the service life of the moving parts of the rifle.

When the rifle would fire, the bullet travelled down the barrel until it passed the gas port.  Gas was tapped from the barrel into the gas port and pressurized a long gas tube on the left side of the barrel.  The gas tube entered the side of the bolt carrier group.  There a piston chamber was created between the back of an internal chamber in the bolt carrier and bolt.  The gas created an internal pressure, pushing the bolt carrier to the rear.  The cam pin is rotated by the cam path in the receiver unlocking the bolt as it moves rearward.  This also acted as the cut off for the gas once the bolt begins its rearward travel venting off the unused gas.  As the bolt carrier moves rearward the fired cartridge case is extracted and ejected from the rifle once the mouth of the case clears the ejection port.  Now the spring loaded buffer returns the bolt carrier group forward with the bottom two lugs stripping off the top cartridge from the magazine, feeding and chambering the round.  Then final movement locks the bolt into the barrel extension.

Perhaps the most disastrous moment in the history of the AR-10 and if any moment defined the failure in the U.S. trial was the catastrophic barrel failure of serial number 1002. This was caused by Sullivan’s decision to use his aluminum barrels with a SS rifle sleeve. Stoner was adamantly opposed to this course of action and he was right.

This gas system eliminated several heavy parts of the traditional piston mechanism including a heavy operating rod.  Recoil was drastically eliminated due to not having the mass of an operating rod and piston slamming into the shooters shoulder.  This decrease in weight of the carrier group increased accuracy as well.  To further lessen recoil in this inline construction rifle, a muzzle compensator was added.  This made recoil with the larger 7.62x51mm caliber round smooth and easy.

The 4th prototype took on more of what we see today in the design of the AR-10/AR-15.  The rifle has two receivers, an upper and lower held on by a front pivot pin and a rear takedown pin.  The receivers were manufactured from state-of-the-art 7075 T6 aircraft aluminum forgings.  The stock and pistol grip were manufactured from foam-filled phenolic resin, which was lightweight, very strong and impervious to the elements, unlike traditional wood.  The rifle was fed from an aluminum 20-round magazine.  For strength, reinforcing ridges were pressed into the sides of the magazine giving it the “waffle” appearance.  These magazines were intended on being disposable in combat.  Due to the light weight of the magazine, soldiers would be able to carry more ammunition in preloaded magazines compared to previous rifles.

Another outstanding feature of the design and one that would certainly decrease weight was the design of a barrel extension for the multi-lug bolt to lock into.  Unlike previous designs, a large chunk of metal surrounds the chamber to contain the pressures of the chamber and afford a location for the bolt to lock into.  The AR-10 barrel extension screwed onto the rear of the chamber and focused the pressure into a small area.  U.S. Patent Number 3,027,672 was granted for the barrel extension on April 3, 1962.

The rifle was very user friendly.  With the shooting hand, the thumb actuated the selector lever and trigger finger actuated the trigger and magazine release button.  The left hand actuated the bolt catch and cocking handle located inside the carrying handle on top of the rifle.  The left hand also loaded and unloaded the magazine.

Close up view of the muzzle compensator found on the early Hollywood rifles. The end is held on by a snap ring that could be removed with the tip of a bayonet.

The rifle appeared futuristic and broke with traditions of what a military rifle was supposed to look and feel like.  Too new for some and those were often the influential people making the decisions on procurement.  Many new designs were tried to make use of new materials such as the use of aluminum barrels.  That came to no avail but shows the type of research and development going on at ArmaLite.

In late 1955, the U.S. Army got their first look at the new AR-10.  It was demonstrated to high ranking officials at the Infantry School at Fort Benning and Headquarters, Continental Army Command at Fort Monroe.  It was ArmaLite’s hope to delay the selection of the new rifle to replace the M1.  The T44 (M14) and the T48 (FAL) had been tested for quite some time and the decision was close.  Using the 4th prototype as the base, 50 rifles were handmade.  The barrels were a controversial issue within the walls of the ArmaLite shop.  Stoner had highly recommended and fought to have standard military grade steel barrels used.  Sullivan however over-ruled his recommendations and they used aluminum barrels swaged around 416 SS rifled liners.

At the 2012 SHOT Show, ArmaLite introduced their new and long anticipated AR-10A family of rifles.  This is an AR-10 that uses the standard magazine rather than the proprietary M14 based magazine that the ArmaLite AR-10B rifles have used since their introduction in 1995.

To trace the history a little, the ArmaLite AR-10B series was introduced to the commercial market in 1995, which was one year after the infliction of the 1994 assault weapon ban that prohibited production of magazines that held more than 10 rounds for commercial purposes.  Former U.S. Army Ordnance officer and President of ArmaLite Mark Westrom had a dilemma on his hands while in development of his AR-10.  He could use the standard AR-10 magazine that was developed in the 1950s, which there were few available, and the new Knight’s Armament Company SR25 magazine, of which there were even fewer in production prior to the institution of the ban.  Another option was the FAL magazine.  The FAL magazine would not work due to a different bullet feed; the feed lips were in the receiver, thus the FAL magazine was not a good candidate.  However, there were tens of thousands of surplus M14 magazines out there.  Westrom wanted his customers to have a legal 20-round magazine and there was only one way to do it: convert his AR-10 magazine well to take the M14 magazine.  The magazine would need a major modification to work as well.  The follower would not actuate the AR-style bolt catch so a patented spring loaded plunger was added to the rear of the follower.  The catch was cut into the left side of the magazine.  The entire bolt catch option was made possible by the groove in the back of the magazine well.  That gave the space for the spring loaded plunger to activate when the last two rounds are in the magazine.  When the bolt carrier group moved to the rear after firing the last round the plunger lifts upward on the bolt catch locking the bolt to the rear.  Due to no stop-notch on the modified AR-10 magazine to prevent it from over-traveling the mag catch, Westrom added a stop rib in the upper receiver that prevents mag catch over-travel.  Westrom offered a magazine conversion service to his customers who would send in their M14 magazines and ArmaLite would convert them to work in their rifle and ship them back.  This worked out very well.

In 2004, the “Assault Weapon Ban” sunset permitted new production of high capacity magazines.  In the intervening years other AR-10-type rifles came to market.  Over the last 5 years alone, many new rifles have come on deck including DPMS, Remington, LWRCI and SIG to name a few of the newly produced 7.62mm rifles similar to that of the AR10-type rifles that took the standard AR-10 magazine.  Then Magpul introduced their PMag L20 magazine that is an original AR-10/SR-25 magazine.  They took over the market with all of these companies.  To date most all of the AR-10-type rifles are shipped with this magazine.

The success of the ArmaLite AR-10B-series is undeniable.  However, there was a part of the market who liked the idea of multiple sources for magazines.  Some of them are diehard Magpul fans as well.  With all the additional companies now offering the AR-10-type design, ArmaLite may very well have lost customers to companies that had the non-proprietary standard magazine.  The modified M14 magazine is a very strong, durable and reliable magazine.  With the ban’s demise, ArmaLite went into production of their own magazine, making it even better than the converted M14 magazine.  There were no functional issues here.  The standard magazine is no more or less reliable than the M14.  In fact, the M14 magazine was steel compared to aluminum.  But the customers have spoken.

The new addition to the AR-10 lineup is the AR-10A. The difference is instead of using the M14 based magazine the new rifle uses the standard AR-10 magazine making it compatible with several other manufacturers’ magazines including original 1950s vintage AR-10 magazines, Magpul, Knight’s Armament Company SR25 magazines and C-Products magazine.

Westrom decided to offer an additional family of weapons to his lineup; the AR-10A to separate it from the AR-10B, which takes the modified M14 magazine.  This required a new magazine well and a modified upper receiver.  The upper receiver had to have the magazine stop notches removed.  With the redesign of the magazine well the rifle would accept the 1950s original magazines, KAC SR-25 magazines, C-Product magazines and perhaps more importantly the new Magpul PMag L20 magazine.

The rest of the rifle remains the same.  The only new parts would be the upper receiver itself, bolt catch and the magazine catch.  For this article a prototype rifle was provided.  It was based on the AR-10A4.  The rifle has a fixed GI stock, flat top upper receiver, ArmaLite full length quad rail system (non free floating) and a 20-inch barrel with A2-style compensator.  There were a few gadgets added to the rifle including an ambidextrous selector lever, KAC front and rear back up sights and a Norgon ambidextrous magazine catch.  On the original rifles, the Norgon ambi-catch did not work.  If you depressed in from the left you would have to pull the magazine out.  It was not compatible with the M14 magazine. However, now with the standard magazine it works perfectly.  There is only one exception; it will not work with the 1950s magazines.  The geometry of the catch is not compatible with the original magazines though it works perfectly with all others.  The optic chosen was a Leupold Mark 4 LR/T 3.5-10x40mm M3 with illuminated reticle mounted on an A.R.M.S., Inc. high throw lever mount.

The original 1950s ‘waffle’ magazine (left) compared to the modified M14 magazine (right), which Westrom used in his AR-10 series introduced in 1995. The M14 magazine is durable and reliable but proprietary to ArmaLite rifles.

Fit and finish is what you would expect from ArmaLite.  Receivers were tight and flawless finish.  The rifle has the two stage match trigger in it and some Tangodown grip panels/rail protectors were added.  When at the range a Harris bipod was used mounted to an A.R.M.S., Inc. throw lever mount.  KAC magazines as well as C-Products and PMags were taken to the range to test for compatibility.

The ammunition for this test was provided by Silver State Armory (SSA).  SSA is known for manufacturing some of the highest quality duty and match ammunition in the industry at competitive pricing.  Silver State Armory just moved to a state-of-the-art facility in Packwood, WA where they have a 100 meter underground range and the facility meets United States Department of Defense requirements to manufacture military contract ammunition.  They manufacture their own brass.  All SSA ammunition is loaded with custom blends of powder geared towards the specific loading.  They offer several loadings in 5.56mm, 7.62mm NATO, 6.8SPC and .499 LWRC.  They are also one of the only ammunition manufacturers in the United States to manufacture armor piercing rifle ammunition in 5.56mm, 7.62mm NATO and 6.8SPC.

The right side of the AR-10A shows the forward bolt assist, fired cartridge case deflector, magazine release button boss, ambidextrous selector lever, Magpul PMag 20LR magazine and KAC rear back up iron sight. The scope is the standard U.S. military issue Leupold Mark 4 LR/T 3.5-10x40mm M3 Illuminate Reticle scope.

There were 400 rounds of Silver State Armory 7.62x51mm 147gr FMJ ammunition fired from a variety of PMag L20, KAC, C-Products and original 1950s waffle magazines.  There were no misfires or malfunctions encountered during testing.  The rifle’s bolt carrier group was lubricated with G96 CLP before firing but the weapon would not be cleaned through the entire test.  Accuracy testing was conducted with Silver State Armory 168 and 175 grain OTM ammunition as well as Hornady Superformance 175 grain OTM ammunition.  There were an additional 200 rounds fired in combination of these match loads.  The rifle averaged between 1 to 1.75 inches at 100 yards.  By margin the best target was 1 inch and that was with the Silver State Armory 168 grain Sierra open tip match ammunition.  This is a very respectable group for a semiautomatic rifle.  Even the ball ammunition was shot sub 2 MOA.

It is this author’s prediction that the AR10-A will take over ArmaLite’s production in the future.  As the new model gains more visibility its popularity will explode.  The AR-10A will be offered in all models.  I would expect more models to be introduced at the SHOT Show in 2013.  The AR-10A is not replacing the existing AR-10B family.  It is an additional family of rifles to the ArmaLite line-up.  It would also be probable if another ban was to commence the original AR-10B family with the modified M14 magazines would resurface dominantly so customers would still be able to have 20-round magazines.  Although it appears clearly the M14 magazine is a stronger and more durable magazine than the original magazine, the standard magazine is more common and offered by several companies.  Keep in mind the original magazines were made out of aluminum and meant to be disposable – not to be used over and over again like the steel M14 magazines.  Whichever way you go, you will not go wrong with any ArmaLite AR-10 family of weapons.

Close up of the markings on the AR-10A rifle. Notice the Norgon ambidextrous magazine catch installed by the author and the heavy texture on the bolt catch making it easy to actuate and grip.

Early in the wars in Afghanistan and Iraq it was clear by the entire sniping community there was a need for a new updated sniper rifle.  Modern semiautomatic rifles show little to no accuracy degradation from the traditional bolt action rifles used throughout the last century.  The use of a semiautomatic sniper system not only would provide the snipers with their existing capabilities but so much more.  Snipers could engage five targets in at least half the time it would take a sniper with a bolt action rifle.  Also, the snipers ability to engage multi-targets is vastly increased.  The sniper also would have 20 rounds of ammunition rather than the 5 of the standard bolt action rifle.  It was time for an update.  Onset the XM110 SASS Program (Semi Automatic Sniper System).

There already existed a weapon in the military system that fit most of the requirements, the U.S. Navy’s Mk11 Mod0 sniper rifle.  The Knight’s Armament Company rifle is based on Gene Stoner and Reed Knights SR25 rifle – a modernized AR-10 if you will.  This rifle began service in 1990 and distinguished itself within the SOCOM community.  Based on the well known M16 weapon system, this makes the user feel right at home and comfortable with the feel, operation and maintenance of the weapon system.  This weapon was ready to go mainstream to enhance a sniper’s ability to do his job more efficiently and enable him to deal with any situation which may arise.

The SASS program was announced by the military in November of 2004.  Several companies submitted entries.  This would include companies such as Knight’s, Remington, DPMS and ArmaLite.  Mark Westrom of ArmaLite, a retired U.S. Army Ordnance officer, entered a version of his proven AR-10 rifle.  He took his standard design and made the needed changes to make his Geneseo, Illinois made rifle compete for the gold.  Westrom and ArmaLite are not new to the military market; they have rifles in service in Canada as well as Israel.  Westrom knew it would be all but impossible to displace the Knight’s Armament Company rifle already in service.

The telescopic stock of the ArmaLite XM110 was replaced with the Magpul PRS (Precision Rifle Stock) which is one of the finest stocks of its type. The PRS has adjustable buttplate as well as cheek piece. Additionally, a rail is located on the bottom to accept a monopod if desired.

The ArmaLite XM110 took the basic AR-10 design ArmaLite has produced since it came to market in 1994 and utilized a telescopic 6-poition VLTOR club foot stock assembly.  The requirement stated an adjustable stock, which could either be a telescopic or a fixed stock with an adjustable buttplate. The rifle was all coyote tan in color per requirement.  The rifle was equipped with a match grade 2-stage trigger manufactured by Chip McCormick.  ArmaLite designed back-up front and rear sights were used along with an ArmaLite designed free floating handguard with quad Mil-Std 1913 rails.  The barrel was chambered for the 7.62x51mm NATO cartridge with a 20-inch 1 turn in 11.25 inches and was equipped with a mount for a Sure Fire sound suppressor.  The gas flow was adjustable permitting normal use, suppressed as well as complete gas shut off.  There was a scope requirement but no particular scope was specified.  ArmaLite opted for the Leupold 3.5×10 match scope which had been used with confidence on the Mk11 MOD0.  The maximum effective range of the rifle was 1,000 meters with a barrel life of 7- to 10,000-rounds depending on maintenance and how it is used.

The AR-10 series produced by ArmaLite uses a modified M14 magazine rather than the original AR-10/SR25 magazine.  The ArmaLite AR-10 was introduced to the market after the U.S. Federal Assault Weapon Ban.  Westrom wanted all of his customers to be able to have high capacity magazines.  There were very few of the original ArmaLite AR-10 magazines or Knights SR25 magazines available in the market and if you could get them they were extremely expensive.  Knowing of the extensive stocks of M14 magazines, Westrom opted to design his rifle around this magazine and making a few modifications that included replacing the follower with one equipped with a spring loaded plunger that would actuate the bolt catch when the rifle fired its last round.  Over the decade of the ban, ArmaLite offered these modified magazines for sale and would convert customer magazines over if they were sent to the factory.  After the sunset of the assault weapon ban, ArmaLite went to work to develop their own magazine, which is based on the M14 design but modified for use in the AR-10.  Currently Westrom offers 5-, 10-, 20- and 25-round magazines.

Monroe County Sheriff Deputy Stephen Warden test fires the ArmaLite SUPER SASS rifle while the author’s 8 year old daughter Sophia spots for him. Warden is a firearms instructor as well as a veteran of both Afghanistan and Iraq.

Also per requirement the rifle was provided in a Hardig polymer case which added over $1,000 to the cost of the weapon system.  Provided were cleaning materials, spare parts as well as a sling.  On September 28, 2005 Knight’s Armament Company was awarded the contract for the M110.

Westrom put much development into his SASS rifle and saw it had potential for other military, law enforcement as well as commercial markets.  Now without the restrictions of the solicitation, Westrom went on to develop his AR-10 Super SASS rifle.  The Super SASS was revealed to the shooting community at the SHOT Show in 2006.  The Super SASS is a suppressor ready rifle.  The adjustable gas system has two settings, one for normal use and another for use with a sound suppressor.  The valve can be moved with the base of a 7.62x51mm cartridge.  The Super SASS was designed to work with the Advanced Armament S3R large chamber suppressor. However, if you are unable to possess a sound suppressor for one reason or another, ArmaLite offers a look-alike which can be mounted on the barrel for cosmetic purposes.  The 20 inch match grade heavy triple lapped barrel is ceramic coated AISI 416R stainless steel with a 1 turn in 10 inch twist optimal for 150 to 175 grain projectiles.  The ammunition suggested by ArmaLite is the 168 and 17grain match loads.  ArmaLite guarantees 1 MOA out of the box on all Super SASS rifles.

The receivers are manufactured from 7175 T-74 aluminum forgings.  The upper receiver is a flattop upper receiver with a Mil-Std 1913 rail.  This rifle features the fairly newly released forward bolt assist.  The upper receiver also has a fired cartridge case deflector preventing fired cartridge cases from hitting a left-handed shooter in the face.  The rifle is equipped with a Precision Reflex Company manufactured gas buster charging handle which prevents rifle gases from coming back at the shooters face when firing the rifle with a sound suppressor on it.  There is a standard A2-style compensator provided on the muzzle.  The bolt carrier group is modified with forward assist notches and maintains the standard manganese phosphate finish.  ArmaLite used the rubber “O” ring reinforcement of the extractor spring.  This is good insurance especially when firing the rifle in the sound suppressed mode.  Suppressors over gas the rifles gas system making it work much faster.  The extra pressure on the extractor increases extractor force giving additional strength in extracting a cartridge case that is slightly optureated still caused by the bolt opening sooner.  The rifle is provided with three rail protectors for offhand shooting.

The SUPER SASS shot like a world class sniper rifle. From a distance of 100 yards the rifle fired a .44 MOA group using 5 rounds of Silver State Armory 7.62x51mm M118 Match ammunition that is loaded with a 168gr open tip match bullet.

The lower receiver utilizes the Magpul Precision Rifle Stock (PRS), perhaps the finest stock of this kind on the market.  The stock has adjustable cheek weld as well as butt plate.  The stock has a club foot design enabling the shooter to place the non firing hand on it to lock the stock into the shooters shoulder.  The bottom of the stock has a short Mil-Std 1913 rail allowing the attachment of a monopod.  The rifle has a National Match two-stage trigger with a first stage of 2.5 lbs and a second stage of 4.5 to 5 lbs.  The rifle was shipped with one ArmaLite 10- and one 20-round magazine.

The rifle was provided with a Leupold Mark 4 3.5 to 10x scope with an illuminated reticle.  This scope has a 40mm objective and is equipped with bullet drop compensator for the 7.62x51mm round with a 168gr projectile.  The illuminated reticle is turned on or off by the user and has 11 increments of brightness.  The scope was mounted in an ArmaLite 30mm scope mount.

The overall stats on the rifle come in with a 20 inch heavy barrel.  The overall length of the rifle is 44.5 inches and weighs in at 12 pounds.  The fit and finish of the rifle was superb.  The receivers were nice and snug.  The rifle is clearly ArmaLite’s crown jewel and for good reason.  The rifle has an effective range of 1,000 meters.  The rifle was tested with Silver State Armory 7.62x51mm 168gr (M118) and 175gr OTM (M118LR) ammunition as well as Hornady .308 Win Superformance Match 175gr BTHP (#8077) ammunition.  The best group shot was with the 168gr Silver State Armory ammunition at .44 inches at 100 yards.  However the other two types of ammunition all grouped between .50 and 1.0 inches.  Recoil was mild compared to many autoloading 7.62x51mm rifles.  The in-line construction of the Stoner weapon system greatly contributes to this enhancement in handling.

Whether military or law enforcement, the tactical sniper would have everything needed in a sniper rifle with the ArmaLite SUPER SASS.  Precision accuracy, reliability, firepower and high quality workmanship are all hallmarks of this rifle.  For the commercial customer whether it be a competitor, hunter or recreational shooter you can own a military grade sniper rifle.

Retired U.S. Army Ordnance Officer Lt. Col. Mark Westrom, President of ArmaLite (right) describes the merits of his SUPER SASS to two Kosovo Army Officers at the Adriatic Sea Defense& Aerospace show in Split Croatia in March of 2011. The SUPER SASS drew quite a lot of interest with snipers who are used to the heavy and high recoil Dragunov sniper rifles. They had never seen a rifle the quality of the SUPER SASS in the former Warsaw Pact countries.

The reintroduction of the AR-10/SR-25 in the early 1990s re-revolutionized the use of semiautomatic rifles as sniper/tactical rifles.  The direct gas system combined with the eight-lug rotating bolt and a free floating barrel made this system sub-MOA with little difficulty or maintenance.  Although the AR-10 was discarded nearly 50 years ago by a biased and self serving U.S. Ordnance Corps in the late 50s, the rifle has come back with a vengeance even though it came out of private industry rather than a government arsenal.  The rest is history.  The AR-10 weapon family has become extremely popular and, like its 5.56mm little brother, proven to be just as versatile.

The AR-10 comes in both rifle and carbine forms.  Telescopic, fixed as well as precision stocks are available.  Rails systems as well as free floating tubes are available as well as conventional handguards.  Like the 5.56mm weapon, the AR-10 is equipped with Mil-Std 1913 rails and therefore compatible with all the accessories from optics to flashlights.  The rifles are offered in fixed as well as flat top upper receiver variations.

At 100 yards, the AR-10T .338 Federal shot consistent sub-MOA groups. This 10 shot group measured approximately .750 inches. There were two flyers due to too much coffee before shooting.

There is one other aspect of modularity the AR-10 has with the AR-15/M16 series of weapons: caliber interchangeability.  ArmaLite, Inc. has introduce the rifle in the standard 7.62x51mm NATO (.308 Win) as well as .243 Win.  Now a third caliber is offered the .338 Federal.  The .338 Federal is a standard .308 Win cartridge case with the mouth expanded to accept a .338 caliber projectile.  Firing a 180 grain projectile, the velocity is a higher 2,830 feet per second compared to a .308 Win caliber firing a 180 grain projectile at 2,600 feet per second.  The .338 Federal also is offered in a 210 grain projectile that has a muzzle velocity of 2,630 feet per second.  Due to the fact the .338 Federal is based on the .308 Win cartridge case and overall length, the .338 Federal cartridges can be used in a standard .308 Win magazine.  The .338 Federal takes advantages of modern propellants which enable the 210 grain 338 Federal projectile to travel 30 feet per second faster than the 180 grain .308 Win projectile.  The .338 Federal cartridge is a proprietary Federal cartridge.  As of this writing, Federal is the only company manufacturing this caliber.  However, if the popularity expands, more manufacturers will add it to their production line.  This cartridge offers more punch and greater range potential than the .308 Win cartridge and can be adapted to any weapon chambered for the .308 cartridge.

ArmaLite was the first manufacturer of auto-loading weapons to chamber up for this cartridge.  Taking their proven AR-10T rifle and modifying the bore and chamber, the rifle is chambered for the .338 Federal.  Due to the characteristics of the .338 Federal cartridge, nothing else was modified other than the bore and chamber. The rifle that was shipped for test and evaluation was equipped with a 22-inch triple lapped AISI 416R stainless steel barrel RH 1:10 inch twist, which will stabilize .338 caliber projectiles from 185 to 210 grain projectiles.  The front sight base has a Mil-Std 1913 rail on top to enable the placement of a folding front sight.  The free floating handguard is manufactured from aluminum and is manufactured by ArmaLite.  The upper receiver is manufactured from a solid 7175 T74 aluminum forging.  The rifle is also equipped with the newly introduced receiver with a forward bolt assist.  Of course the bolt carrier has ratchet notches machined into the right side of the carrier to function with the forward assist. To accommodate left handed shooters a fired cartridge case deflector has been added to the upper receiver. The upper receiver is a flat top upper receiver with a Mil-Std 1913 rail for mounting optics.

Monroe County Sheriff Deputy Stephen Warden test firing the AR-10T. More recoil is noticed compared to the .308 Win counterpart, though not much. Credit should be given to the inline construction of the Stoner designed direct gas operating system.

The lower receiver is manufactured from a solid 7175 T73 aluminum forging.  The trigger used is ArmaLite’s National Match 2-stage trigger (first stage 2.5 pounds and the second stage is 4.5 pounds).  This trigger proved to be excellent allowing precision trigger control.  A standard M16A2-length stock was provided.  The magazines are based on the M14 magazine and may take M14 magazines and convert them into AR-10 magazines.  ArmaLite has manufactured their own magazines offering several enhancements over the M14 converted magazines.  The ArmaLite manufactured magazines are offered in 5, 10, 20 and 25 round capacities.

The rifle was provided with a Leupold Mark 4 3.5 to 10x scope with an illuminated reticle.  This scope has a 40mm objective and is equipped with bullet drop compensator for the 7.62x51mm round with a 168gr projectile.  The illuminated reticle is turned on or off by the user and has 11 increments of brightness.  The scope was mounted in an ArmaLite 30mm scope mount.  The ammunition tested was the Federal Fusion .338 Federal 200gr projectile.  Due to cost of the ammunition, 100 rounds were fired in this evaluation.  There were no malfunctions during firing.  Recoil was noticeably more than the standard 7.62x51mm cartridge.  The groups printed consistently between 3/4 to 1 MOA.  Though the day of the test was rainy and drizzly, the accuracy is certainly acceptable for any tactical application or hunting application required of it.  There are distinct improvements and justifications to shoot the .338 Federal over the standard .308 Win however, due to the cost, the .338 Federal may never see its full market potential.  The .338 Federal is strong enough for any North American game and that may be its niche.  We will just have to wait and see.

However, in the late 1950s a rifle was designed by Eugene M. Stoner at ArmaLite, Inc. called the AR-10.  ArmaLite was a division of Fairchild Engine and Aircraft located in Hollywood, California.  This revolutionary rifle was truly “Tomorrow’s Rifle Today,” that was more true than anyone knew back then.  Although it never had a chance to compete head-on with the M14 for the next U.S. infantry rifle due to Army politics, as well as the deep rooted thought of a rifle having to be made from steel and wood, the AR-10 did get noticed.  During its limited testing it was known to be the most accurate auto loading rifle made as said by the testers from Ordnance Corps.  Limited numbers of AR-10 rifles were manufactured in the Netherlands by Artillerie-Inrichtingen.  They were manufactured for Dutch Army trials as well as sold in limited numbers to some other countries including, Sudan, Cuba, Italy, Guatemala and Portugal.  As predicted, the M14 was adopted and the AR-10 was tossed in the Ordnance Corps scrap heap.  The requirement came down to scale the AR-10 down to a .22 caliber and the AR-15 was born.  The rights were sold for the AR-15 as well as the AR-10 to Colt’s Patent Firearms Manufacturing Company.  Colt went on to produce the AR-15 but ignored the AR-10 design.  That was left for other companies to capitalize on.  To trace the AR-10 lineage to today’s most advanced sniper rifle we must skip ahead nearly 30 or so years ahead to 1991.

In November of 1991, a Mission Needs Statement was drafted for an Enhanced Sniper Support Team Weapon (SSTW).  This was written by Lt. Col. David Lutz while serving as the Program Manager for Infantry Weapons at MARCORSYSCOM at Quantico, VA.  This documentation was an effort to restart a cancelled Designated Marksman Weapon program (DMR) based on the M14 which could not be made to do all the things needed in a logistically supportable package acceptable to the Fleet Marine Forces.  Its requirement document was weak because it totally lacked objectivity in doing a mission analysis or seeking other viable solutions.  At the time, the current SSTW was the M16A2 rifle.  This weapon supported the M40A1 sniper rifle in the two man scout sniper team.  The M16A2 SSTW was used to engage close-up targets and provide rapid fire suppressive fire if needed.  Some noted deficiencies were the M16A2’s poor interface with the soldier when having optics mounted, including night vision.  The current issue M855 ball ammunition did not meet the accuracy specifications of a SSTW.

USMC snipers firing the Mk11 Mod 0 on the range. Note the use of the suppressor as this is commonly used on the rifles in the field.

The enhanced SSTW would fill the role of a 0 to 600 meter intermediate range sniper rifle.  It would have ammunition interchangeability with the M40A1 7.62x51mm sniper rifle and it would have the ability to mount a sound suppressor.  Optics would be mounted in-line with the shooter’s eyes for a comfortable mount.  This rifle will also have to overcome current problems with the unit, direct, general, and depot support problems (availability and maintainability) long associated with the hand-built and Marine Corps customized M40A1.

Lt. Col. Lutz recalls that he knew of (5 each) Dutch NATO AR-10s that were in a bunker at Picatinny Arsenal from when he was stationed there during 1980-83.  So he had one of his successors, USMC Liaison Officer Maj. Dody Knootz, pick out one that shot the best and “temporary loan” it to them at Quantico.  Several modifications were made with the most significant being the carrying handle cut off and a weaver rail attached to the upper receiver.  The AR-10 had some of the improved M16A2 components added to it including the pistol grip and handguards.  All this was to make it look like and use A2 service rifle parts and training.  Additionally, they removed the AR-10’s faux muzzle, which incorporated a grenade launching spigot, exposed its skinny barrel and threaded muzzle.  Lutz recalls sending the upper to Phil Seberger to have a suppressor made & fitted to it.

As recalled by Lutz, as a concept demonstrator it was a success.  “When my general came out to fire it he brought with him his Australian Army Liaison Officer, a full colonel.  My general was reluctant to fire the weapon as I presented it to him, and handed if off to the Australian Colonel.  Offhand, the Colonel hit a steel gong at 100 yards with 20 of 20 shots (suppressed).  When he handed the rifle back to my general, he said “General, this is the finest rifle I have ever fired.”  When the General handed the rifle back to me, he said “Dave, you have a program.”  I guess the rest is history…”  Though the concept was sound, the Marines or big army were not ready for a semiautomatic sniper rifle, at least not yet.  So the AR-10 lay dormant once again until the early 1990s.  Even though the original DMR program failed, the STSW maintained life in the requirement and allowed Rifle Team Equipment builders at Quantico to produce more prototype M14 based variants as “interim measures.”  This eventually took on a “life of its own,” and an M14 based program eventually found traction as the M39 Enhanced Marksman Rifle (EMR).  However, the M39 is one of the weapons being replaced by the Marines recent purchase of M110s.  The M110 was inherently able to meet the STSW requirement for mounting of Night Vision without lose of zero, sound suppressor integration, M16 ordnance maintenance and training commonality, supply system commonality and cross-service weapon commonality.

The name Eugene Stoner, although not as well known as Browning, is just as significant in the history of the gun.  Stoner’s design is the longest service rifle in U.S. military history.  During Stoner’s ArmaLite days his goal was to develop 7.62x51mm weapons.  He was very fond of his direct gas system.  After the M14 was selected, the future was only in the smaller caliber round so Stoner went on to develop other rifles to fire the 5.56mm cartridge including the AR-18 and the Stoner weapon series.  He never quite forgot his AR-10.  In the early 1990s, Stoner went to work with C. Reed Knight, Jr., the president of Knight’s Armament Company.  The union spawned the rebirth of the AR-10.  This would be the SR-25 (Stoner Rifle-25 (15+10)).  This rifle would be an AR-10 but would take on the advancements of the M16A2 rifle and maintain 60% parts compatibility.

Right side of the M110 rifle receiver. Notice the ambidextrous bolt release above the magazine release as well as the ambidextrous safety lever. The U.S. markings are on the magazine well.

Released in the early 1990s, the SR-25 Match Rifle was equipped with a 24-inch Remington 5R match grade barrel – the same barrel blanks used on the M24 sniper rifle.  The heavy barrel was free floating with a fiberglass handguard.  The rifle was equipped with a flat top upper receiver with the Mil-Std 1913 rail and the receivers were made from aluminum extrusions.  The rifle was equipped with a 2-stage match grade trigger.  The bolt carrier group kept with the original AR-10 in that it was chrome plated and it also sported the captive firing pin retainer pin.  These were not mass produced rifles.  The uppers and lowers were mated together and had matching serial numbers to identify them.  They were specifically designed around the 168gr OTM Match cartridge.  Using this factory load, the ogive of the bullet set right on the rifling.  This is something match shooters want to accomplish due to not wanting the bullet to “jump” into the rifling thus maintaining control of the projectile right from the moment of chambering.  The original rifles used the standard “waffle” pattern 20-round magazine and later a steel magazine that looked more like an M16 20-round magazine in appearance.  The SR-25 was sold initially through commercial channels that funded R&D.  Every SR-25 was test fired at the factory and provided with a target.  Knight guaranteed that this rifle would fire 1 MOA or under with factory ammunition.  Gene Stoner would work with Knight up until his death in 1997.

The SR-25 quickly gained its reputation for precision accuracy and reliability and its versatility and benefits were appreciated right away by the special operation forces.  SOCOM liked the idea of having a semiautomatic rifle that held 20 rounds of ammunition and rivaled the M24 and M40A1 bolt action rifles.  They also liked that you could engage multiple targets in less than half the time they could with a manual bolt action rifle.

After more than 40 years, the AR-10 would have its day.  In May of 2000, the U.S. Navy and SOCOM adopted the SR-25 as their new Mk 11 Mod 0.  This would be follow by another contract in 2007 for 9.9 million dollars with the need from the Global War On Terrorism.  The Mk11 had some departures from the original design.  Designed to meet the SOCCOM requirement, the rifle was designed to fire the M118 and M118LR match grade 7.62x51mm NATO ammunition.  The Remington barrel was replaced with an Obermeyer barrel and was shortened to 20 inches and equipped with a mount for a quick detachable sound suppressor also developed by Knight’s Armament Company.  The 11.35-inch Rail Accessory System free floating handguard provided quad Mil-Std 1913 rails enabling attachment of any given number of accessories including night vision, lasers, tactical lights and bipods.  The standard M16A2 stock and pistol grip are used for parts commonality.  A flip up front sight was added to the gas block as well as KAC’s fully adjustable back-up iron sight was added.  The rifle was equipped with 20-round magazines, a Leupold Vari-X mil dot scope with detachable rings and a Harris bipod.  The Mk11 weighs 15.3 pounds unloaded and has an overall length of 45.4 inches.  The Mk11 would see action with U.S. Special Operations troops all over the world.  The weight of the complete Mk11 Mod 0 with the Leupold 3.5×10 scope & SIMRAD adapter, bipod adapter with LM type S Bipod is 13.7 pounds.