The Story

What is an AR-15?

The ArmaLite AR-15 is a gas-operated assault rifle manufactured in the United States between 1959 and 1964 Designed by Eugene Stoner, L. James Sullivan, and Bob Fremont under American gun manufacturer ArmaLite in 1956, it was based on the AR-10 rifle. The ArmaLite AR-15 was designed to be a lightweight rifle, firing a new high-velocity, lightweight, small-caliber cartridge allowing infantrymen to carry more ammunition.

After World War II, the United States military started looking for a single automatic rifle to replace the M1 Garand, M1/M2 Carbines, M1918 Browning Automatic Rifle, M3 "Grease Gun" and Thompson submachine gun. American weapons designers concluded that an intermediate round was necessary, and recommended a small-caliber, high-velocity cartridge.

ArmaLite entered the competition late, hurriedly submitting several AR-10 prototype rifles in the fall of 1956 to the United States Army's Springfield Armory for testing.

The ArmaLite AR-10 featured an innovative combination of a straight-line barrel/stock design, a new patent-filed gas-operated bolt, forged aluminum alloy receivers and with phenolic composite stocks resulting in a small arm significantly easier to control in automatic fire than other infantry rifles of the day. It had rugged elevated sights, an oversized aluminum flash suppressor and recoil compensator, and an adjustable gas system. The final prototype, featured an upper and lower receiver with the now-familiar hinge and takedown pins, and the charging handle was on top of the receiver placed inside of the carry handle. For a 1950s 7.62×51mm NATO rifle, the AR-10 was incredibly lightweight at only 6.85 pounds (3.11 kilograms) empty. Initial comments by Springfield Armory test staff were favorable, and some testers commented that the AR-10 was the best lightweight automatic rifle ever tested by the Armory.

In the end, the United States Army chose the T44, which entered service as the M14 rifle, which was an improved M1 Garand with a 20-round magazine and automatic fire capability. The U.S. also adopted the M60 general purpose machine gun (GPMG).

As a result, the Army was forced to reconsider a 1957 request by General Willard G. Wyman, commander of the U.S. Continental Army Command (CONARC), to develop a .223 caliber (5.56 mm) select-fire rifle weighing 6 lb (2.7 kg) when loaded with a 20-round magazine. The 5.56mm round had to penetrate a standard U.S. M1 helmet at 500 yards (460 meters) and retain a velocity in excess of the speed of sound, while matching or exceeding the wounding ability of the .30 Carbine cartridge. This request ultimately resulted in the development of a scaled-down version of the ArmaLite AR-10, called the ArmaLite AR-15 rifle.

In 1958, ArmaLite submitted ten AR-15s and one hundred 25-round magazines for CONARC testing. The tests found that a five to seven man team armed with AR-15s had the same firepower as an 11-man team armed with M14s and soldiers armed with AR-15s could also carry three times more ammunition than those armed with M14s (649 rounds vs. 220 rounds). The AR-15 was found to be three times more reliable than the M14 rifle.

However, General Maxwell Taylor, then Army Chief of Staff, "vetoed" the AR-15 in favor of the M14. In 1959, ArmaLite—now frustrated with the lack of results and suffering ongoing financial difficulties—sold its rights to the AR-10 and AR-15 to Colt.

After acquiring the AR-15, Colt promptly redesigned the rifle to facilitate mass production. Based on the final ArmaLite design, most notably, the charging handle was re-located from under the carrying handle, like the earlier AR-10 to the rear of the receiver, like the later M16 rifle. Colt then renamed and rebranded the rifle "Colt ArmaLite AR-15 Model 01". After a Far East tour, Colt made its first sale of Colt ArmaLite AR-15 rifles to Malaya on September 30, 1959. Colt manufactured their first batch of 300 Colt ArmaLite AR-15 rifles in December 1959. Colt would go on to market the Colt ArmaLite AR-15 rifle to military services around the world.

Why build one?

Ente built his Prototype AR-15 for less than $1700 USD with new & reproduction parts.

(Tools not included in that price.)

How did he do it?

Upper Receiver Mayhem Machine Tool $430

601 Sight Assembly AR15Sport $43

601 Ejection Port Cover AR15Sport $25

Bolt Carrier Group Brownells $130

Prototype Firing Pin Retainer AR15Sport $8

Gas Tube Palmetto State Armory $13

Barrel Harrington & Richardson $260

Muzzle Device Brownells $30

Lower Receiver Harrington & Richardson $140

601 Safety Selector AR15Sport $50

Safety Selector Detent AR15Sport $1

Safety Selector Spring AR15Sport $1

601 Bolt Catch AR15Sport $50

Bolt Catch Detent AR15Sport $1

Bolt Catch Spring AR15Sport $1

Bolt Catch Roll Pin AR15Sport $1

Magazine Catch Spring AR15Sport $1

601 Magazine Catch AR15Sport $20

601 Magazine Catch Button AR15Sport $20

601 Takedown Pins AR15Sport $32

Hammer AR15Sport $19

Hammer Spring AR15Sport $2

Disconnector AR15Sport $6

Disconnector Spring AR15Sport $1

Trigger AR15Sport $19

Trigger Spring AR15Sport $2

Trigger Guard Roll Pin AR15Sport $1

Hammer & Trigger Pin AR15Sport $15

Trigger Guard AR15Sport $17

Buffer Detent AR15Sport $2

Buffer Detent Spring AR15Sport $1

Receiver Extension Assembly Luth AR $50

Magazine Harrington & Richardson $40

Prototype Stock Screw AR15Sport $8

Furniture Set CheatingDeathCustoms $250

Total: $1693

After it was completed he used headspace gauges to check the chamber clearance to ensure the rifle was safe to operate.

Accessories

Cleaning Kit DevilDogDepot $19

Sling USGI M1 Sling $20

After a few months of research, careful planning, sourcing parts and tools, the build was finished.

A list of parts and tools used can be found below. For those who want to build their own CAR-15.

Thank you for reading if you made it this far!

-Ente & Maltz

Founders of Functional Reserve Militia