The Armalite AR-10: From The Beginning

The Armalite AR-10: From The Beginning


Early in 1956, two rifles were submitted to Springfield Armory for testing.  They were serial numbers 1002 and 1004.  Almost immediately failures erupted.  These would include broken extractors, failures to feed, bolt over base, failures of the muzzle compensator, bent gas tubes and pierced primers.  The rifles were sent back to ArmaLite to have the problems corrected.

In 1957 the rifles were returned to continue the testing.  ArmaLite corrected the issues the best they could given the time constraints.  The muzzle compensator material was changed to titanium.  However, if there was one single event in the history of the testing that doomed the AR-10 from being the next U.S. service rifle it was the catastrophic failure of the barrel on serial number 1002.  During a full auto test, on round 5,564 and 109th in the last portion of the test, an 8 inch long rupture occurred on the left side of the barrel and hand guard just missing the shooters hand.  The bullet exited out the left side of the rupture.  Metallurgical investigation showed the 416 SS liners could not handle the strain.  The entire surface was covered with stress cracks.  Stoner worked all weekend to produce standard steel barrels to complete the test.  The finger pointed at Sullivan.  He made a decision against his Chief Engineer when he had no gun design or metallurgical background to base the decision.  It was a fateful one.

Last production Portuguese model produced by A.I. Perhaps the U.S. trials would have been different if this was the rifle tested.

The Springfield report was issued stating it would take at least 5 years to properly develop the AR-10 and that it basically was nowhere near ready for prime time. Of course ArmaLite disagreed.  Charlie Dorchester stated that, “One of the Springfield test staff fired the AR-10 and I was looking over his shoulder and he wrote on the report that this was the best lightweight automatic rifle ever tested at Springfield Arsenal.  But a few minutes later his supervisor looked at the statement and erased every word.”

There was more to consider on part of Springfield Armory.  They had to protect their T44 right or wrong.  Too many jobs and high ranking careers were on the line if Springfield stopped producing rifles and shut down for a new home grown rifle or a foreign made rifle.  This would cloud their judgment and prevent the American soldier from having the finest weapon but they felt that was a proper trade off in their minds.  This same attitude would later be their final downfall after the botch-up of the M16 program.

The AR-10 had suffered from several disadvantages through no fault of its own.  First, it entered the competition too late in the game.  It was simply not ready.  The rifles it was competing against had years of refinement in their favor.  ArmaLite would continue to refine the AR-10 but not for the U.S. Government.  But they also needed somebody to sell and build it.  Fairchild divided the world into four different sections.  Sam Cummings would get Central and South America, Sub-Sahara Africa and Scandinavia minus Denmark.  Cooper and McDonald would get Asia.  SIDEM International would get Europe and North Africa and Fairchild would get the U.S.

Finding a factory to build the AR-10 was handled by Boutelle.  He had previous dealings with a Dutch company in Hembrug-Zanndam called A.I. or Artillerie-Inrichtingen.  This company was jointly owned by the Dutch government and private industry.  They had the capacity to build the rifle.  Their director, Fried Jungeling, first heard of the rifle in a Time magazine article called “The Aluminum Rifle.” The contract was signed on 4 July 1957. The contract contained that A.I. would produce rifles licensed from ArmaLite and would sell through their agents.  They would pay a royalty on each rifle produced and build 2,000 rifles within a year of the signing of this agreement and then 10,000 per month after.  At this time, L. James Sullivan and Art Miller came to work for ArmaLite.  Miller became Stoners assistant and was sent to Holland to work with A.I. on rifle manufacturing.  A.I. had many start-up issues and were slow by western standards.  They wanted to take their time and do the job right.

Eugene Morrison Stoner holding his prototype SR-25 in an orange grove in Florida. Stoner designed weapons will be with us for the next 20 + years at least.

There were several initial production changes to the AR-10 to get it ready for production.  These would include moving the gas tube to the top of the rifle from the left side and a gas valve to be added in front of the front sight base.  The muzzle compensator was removed and replaces with an open prong flash suppressor.  Fluted steel barrels were used to decrease weight of the rifle and a steel butt plate was added.  The handguards were brown and manufactured from fiberglass woven over a brass tube with several vent holes.

The first sale made of the AR-10 was 2,500 rifles at $225 each to the Sudan.  These rifles had a slight modification to the barrel: they had a stainless steel barrel with a bayonet lug.  The rifles were delivered in October of 1958 on schedule.  An additional 200 to 600 rifles were sold to Guatemala.  These numbers were far smaller than ArmaLite hoped for or needed to keep the company afloat.  ArmaLite was in financial crisis.

A.I. was responsible for getting the rifle competed by the Dutch Army.  In the final down-select, the AR-10 was competing with the FAL rifle.  The baseline rifle for comparison was the M1 Garand rifle.  Again, the AR-10 was dealing with the fully developed FAL rifle – a similar situation played out with the U.S. Army.  The FAL was manufactured by a world renowned rifle manufacturer and the UK and Canada had already selected the FAL.  For all intents and purposes, the AR-10 was still considered a prototype rifle.  A.I. delivered 20 rifles to the Dutch Army for testing.  A request was made to submit later improved rifles for testing but the Army refused the swap.  The testing done by the Dutch Army found major parts breakage.  The rifles shot very accurate but that was not enough, the FAL won in Holland.

The rifle was tested by South Africa where it competed against the FAL, Spanish CETME (G3) and the Swiss StG57.  The stakes were extremely high as ArmaLite and A.I. were in serious financial trouble.  This was not only a sale of rifles but a license to produce the rifles in South Africa.  FAL again won but the AR-10 came out second. As the saying goes, second place is the first loser.

The A.I. produced AR-10 on top. This was the Portuguese version, the last of the production compared to the 2013 ArmaLite AR-10A on the bottom. How far it has come but then in a way it is very similar to its late 1950s father. The new AR-10A will feed the late 1950s waffle magazines.

The last sale made was to Portugal.  SIDEM sold 1,200 rifles in 1960 that grew to 4-5,000.  The rifle had some changes including a telescopic charging handle, which also worked as a forward assist and widening of the bolt locking lugs to strengthen the bolt.  There was a provision to mount a bayonet at the 12 o’clock position and the chamber was chrome plated.  The Portuguese liked the AR-10 very much and used them in their colonies in Angola and Mozambique.  The AR-10 was selected over both the FAL and the G3.  Shortly after the sale, A.I stopped production of the AR-10 and the Portuguese were cut off and no longer able to procure any more of the rifle.

ArmaLite went on to work on the new high velocity caliber AR-15.  Many of the refinements made on the AR-15 were carried over to a modified AR-10 and it was renamed the AR-10A.  In 1959, the rights to both the AR-15 and the AR-10 were sold to Colt’s.

In 1961 Stoner left ArmaLite to go to work for Cadillac Gauge and Art Miller became the Chief Designer.

After Boutelle left, Fairchild sold ArmaLite to George Sullivan in 1962.  With funding by Capital South West, ArmaLite Corporation was now called ArmaLite, Inc.  The Fairchild winged Pegasus was replaced by a lion.  Then in 1971, Charlie Dorchester bought out Capital South West and became Chairman of the Board with Rick Klotzly as President.  Then in 1980, ArmaLite was sold to John Ugante.

Generation 3
The AR-10 was in complete obscurity from 1959 until its reappearance in 1993.  Stoner never forgot his AR-10 design and always preferred to design 7.62mm weapons.  He teamed up with C. Reed Knight II at Knight’s Armament Company in Vero Beach, FL.  There he took the refinements of the M16A2 rifle and built a new AR-10 called the SR-25.  SR stood for Stoner Rifle and the 25 came from adding the 10 in AR-10 and the 15 from AR-15.  The new SR-25 used an M24 barrel blank and was guaranteed to fire 1 MOA out of the box.  The SR-25 touted 60% parts compatibility with the M16A2 rifle.  The AR-10 was back and this time with a vengeance.  It would go on to be adopted by the United States Special Operations Command as the Mk11 Mod 0 sniper rifle and be used by the most elite warriors on the planet.  Then it would go on to be adopted as the M110 SASS (Semi Automatic Sniper System) and replace the outdated M24 bolt action sniper rifles in the U.S. Army.

Close up view of the markings of Gene Stoners prototype SR-25, the AR-10 he could never forget.

ArmaLite would have a rebirth as well.  Former Army Ordnance Officer Mark Westrom bought Eagle Arms.  There he began development of his own AR-10 type rifle choosing to build a rifle based on the SR-25 subsystems.  The receivers and bolt carrier groups would be compatible with the SR-25.  This would give him a customer base for spare parts as well.  But at the time the Clinton Assault Weapon Ban was in effect and high capacity magazines could not be sold to the public.  Westrom wanted his customers to have a 20-round magazine so he modified the M14 steel magazine to work in his rifle, and Westrom purchased 6,000 pre-ban 20-round magazines from LMO to ensure his future sources.  During this time, in 1996, Westrom purchased the trademark ArmaLite along with some other intellectual property.  He introduced his new rifle as the AR-10 and makes his own AR-10A, which uses the original AR-10/SR-25 magazine.  Westrom’s company has sold AR-10 sniper rifles throughout the world.

Generation 4
The newest and most advanced version of the AR-10 is manufactured by Karl Lewis, President of Lewis Machine and Tool.  His LM8MWS represents the most advanced and modular rifle in the family of weapons.  His departure is the use of his own design monolithic upper receiver.  The receiver is a single piece machined from a 7075 T6 forging with a continuous Mil-Std 1913 rail on top of the receiver.  The LM8 design offers removable rail segments that allow the user to put rails wherever they are needed and as much is as needed.  This decreases weight and the threat to damage of unused rails.

What truly makes this the next generation is the ability to remove the barrel at user level and replace the barrel with a 13.5, 16, 18 or 20 inch barrel.  This enables configuration of the rifle to whatever mission it must accomplish.  This is all by removing two Torx bolts.  All that is needed is a torque wrench and T30 Torx bit.  The bolts are removed, the barrel slides out and the desirable barrel is replaced in the receiver.  Then 140-inch pound torque and the rifle is ready for action.  Not only can you change out barrel lengths but calibers as well.  The rifle can be chambered in 7.62x51mm/.308 Win, .243 Win, .260 Rem, 7mm-08 Rem, 6.5 Creedmoor or .338 Federal.  The rifle can be had in semiautomatic only or selective fire.  One version of this rifle has been adopted by the British army as their Sharpshooter rifle, the L129A1.

There are more than 20 different manufacturers making some form of the AR-10 as of this writing.  The rifles see use throughout the globe.  The rifle is offered in the traditional direct gas impingement such as ArmaLite, LMT and KAC or in a short stroke piston such as LWRCI, SIG and H&K.  They are made for any possible use from military combat rifles, sniper rifles, competitive rifles, self defense, hunting and target shooting.  This design does all that.  Stoner never lived to see how the rifle he designed in the late 1950s, and was virtually ignored by the industry, would go on to serve his country in the global war on terrorism and become one of the most popular rifles in American history.  This is a testament to his genius.