Guns Magazine, April, 2001 by Robert Bruce
In an era of hard-hitting, post-World War II battle rifles, Eugene Stoner's innovative design led the way into the modern age of small arms.
Eugene Stoner, newly hired chief engineer for the California-based ArmaLite Corporation, began working on an interesting prototype battle rifle in 1955 incorporating a number of features inspired by Melvin Johnson's remarkable light machine guns.
External similarities to the Johnson Light Machine Gun included straight-line layout, pistol grip, detachable box magazine and high-mounted sights. Inside, at the heart of the weapon, was Johnson's patented eight-lug rotary bolt, allowing strong positive locking into a barrel extension.
Stoner leaped over two centuries of firearms tradition by putting this bolt system inside a relatively weak but very light and inexpensive aluminum alloy receiver. Further weight savings over traditional autoloading designs were realized in fiberglass-reinforced plastic furniture and Stoner's patented update development of a direct gas system.
By early 1957, three successive prototypes had been built, tested, and improved upon to the point where serious efforts could be made to find a production facility to handle quantity manufacture. ArmaLite/Fairchild partner Richard Boutelle used his inside track with the Dutch to cut a deal with the government-owned firm of Artillerie-Inrichtingen, which reportedly, invested the equivalent 2.5 million U.S. dollars into state-of-the-art machinery and tooling.
Unfortunately, all was not well over in Holland where delays were soon being experienced because of conversion from inches to millimeters, modifications resulting from field trials, and a bit more than usual debugging of the production process. Because of this, several large orders were lost to the excellent Belgian-designed FAL.
Seemingly undaunted, Stoner kept up ArmaLite's commitment to the project by fabricating an AR-10 family of weapons utilizing a common core of parts and assemblies to the greatest practical extent. These included a shortened carbine, a sniper rifle, a belt-fed light machine gun, and a heavy-barreled squad automatic weapon.
In spite of many impressive demonstrations worldwide, the radical new AR-10 rifle just didn't sell. The final blow for Artillerie-Inrichtingen came when even the Dutch Army rejected it, joining the parade of most other European nations who were fielding the FAL.
Here Comes Colt
In 1959, ArmaLite revoked the Dutch license and awarded it to the famous American gunmaker Colt. This arrangement proved mutually beneficial in that the stodgy and financially troubled Colt got a exciting new product while ArmaLite was now associated with an American-based company having a long and well- established reputation for sporting, police and military guns.
What followed for the AR-15 is a colorful story that should be well known to military rifle enthusiasts. The ArmaLite/Colt rifle, ultimately chambered in .223 has confounded most of its critics to become, as the M16A1 series, the standard issue assault rifle for the U.S. Armed Forces and a host of allied nations. There is every indication that this will remain true well into the 21st century.
As for the AR-10, somewhere between 5,000 to 6,000 production copies of all models were made at Artillerie-Inrichtingen. Amid some dark speculation about the CIA buying up a bunch for various spooky programs, ArmaLite's openly confirmed large deliveries were only to Guatemala, Sudan and Portugal, totaling about 3,000.
In the early 1980s the American firm Paragon Sales and Service of Romeoville, Ill., bought from Artillerie-Inrichtingen a quantity of original selective-fire AR-10 rifles and spare parts sets. Some 200 parts sets were assembled on Telko Inc.'s new machined-aluminum semiauto receivers for sale to the general public as the "XM-10." These were quickly snapped up despite a $1,200 price tag.
Field Test Notes
The AR-l0's sights are tried-and-true aperture rear and post front, protected against damage by the sides of the forged aluminum carrying handle and milled steel "ears" on the front riser assembly. They are easily and quickly adjusted for windage and elevation with the two large knurled drums located on the carrying handle/sight rail.
The distinctive stamped waffle-pattern aluminum magazines are quite flimsy and so light it is reported that empty ones have a tendency to remain in place even after the mag release is depressed. Also, the feed lips are notorious for sustaining terminal damage in even moderately rough handling.
The magazine release button is easily reached with the index finger of the right hand even while maintaining a good hold on the pistol grip. However, the button is exposed in a vulnerable position above the surrounding receiver. This can easily mean inadvertent loss of a full mag when energetically carrying out any variety of military duties.
The selector switch is well located just above the pistol grip on the left side of the lower receiver and can be operated by a thumb without having to release the gripping hand.
Cocking the AR-10 takes a bit of getting used to. While most shooters are accustomed to grabbing a side-mounted cocking handle (like the M2 carbine's) or even drawing back on the little charging handle on the M16, the experience of inserting a knuckle into the AR-l0's carrying handle slot is a bit awkward at first. To compound the problem, the charging handle -- looking for all the world like an extremely disoriented trigger -- has to be pressed downward a bit to unlock before it can be drawn rearward.
The trigger pull on factory built AR-l0s has been described as "marginal to poor." For anyone who is not an accomplished target shooter, the gun's trigger release will be entirely satisfactory as military rifles go.
The AR-10, like the Belgian FAL and the German G-3, has a couple of virtues that are immediately apparent on firing. Their straight-line buttstock, pistol grip, and high sights all contribute to fast, instinctive handling and little barrel movement on firing.
The optional heavier plastic composition foregrip with sheet metal extender and light folding bipod make the gun about 2.5 lbs. heavier than a standard rifle, putting weight a bit forward of the regular balance point to minimize climb in rapid fire from a number of unsupported positions.
The AR-10 really shines when the bipod legs are dropped into the dirt and firing begins from the prone supported position. The rifle stayed right on target shot after shot. Even on full auto, it behaved well as long as a tight hold was maintained in the classic auto rifle manner; right hand on the pistol grip, left on the comb of the buttstock, and cheek pressed tightly against that hand.
Goad News and Bad News
The AR-10 fires from a closed bolt (when the trigger is pulled, the bolt is already fully forward and a round is locked in the chamber), which is good for accuracy. However, this system is prone to overheating and "cook-off" when fired full-auto for even a relatively short duration.
Unlike the Soviet AK-47 and the German G-3, the AR-10 is provided with a bolt hold-open device that keeps the action open after the last round in the mag is fired. This is quite useful in operation as the locked open bolt instantly signals the gunner that it is time to insert a fresh mag. A potentially fatal second or two is also saved in not having to cycle the operating handle -- just hit the bolt release and the rifle is ready to shoot again.
With one notable exception, field stripping and maintenance are fast and easy thanks to the simplicity of the parts and the hinged receiver that allows instant access and easy reach into remote corners. No special tools are required for pushing through the takedown pins. These stay locked to the receiver so you don't have to paw around in the dirt or snow to recover them.
All this having been said, there is perhaps no one who has ever gotten an AR-10's or M16's chamber extension area, forward of the bolt locking lugs, properly cleaned and decarbonized without going through extraordinary contortions accompanied by foul cursing.
Despite these misgivings, the ArmaLite AR-10 is an extremely interesting and innovative main battle rifle that is arguably as effective and capable as most of its better-known counterparts worldwide. Think about what might have happened had it not been for administrative and technical problems surrounding startup production in Holland. It is not unreasonable to speculate that Stoner's AR-10 could well have taken a place among the "Big Four" military rifles of the early Cold War period; FAL, CETME/G3, M14, and AK-47.