1958....
March: Ten AR-15 rifles chambered in .222 Special are delivered to Fort Benning for the Infantry Board field trials. Due to the changes required for the new .224E2 Winchester cartridge, the Winchester LWMR is not ready. However, a number of new T44E4 (pre-production M14) rifles are included as a control. Stoner is allowed to participate since no instruction manuals are yet available for the AR-15. Embarrassingly, the T44E4 rifles turn in a malfunction rate of 16 per 1000rds. In contrast, the AR-15 displays a malfunction rate of 6.1/1000. Oddly, after all of the trouble to coordinate the development of the competing cartridges, the .224E2 Winchester still fails the 500 yard helmet penetration requirement. The tests are re-run with the .222 Special, which succeeds.
July: Winchester finally delivers their LWMR to Fort Benning for testing.
During rain tests at Aberdeen, examples of both the AR-15 and the LWMR experience burst barrels. The combination of water in the bore and the heavily fluted barrels used by both candidate rifles prove too much. Both manufacturers respond by providing unfluted barrels for subsequent prototypes. Seizing upon the issue, Dr. Carten begins a campaign to support development of an alternate .256 SCHV (6.35mm) cartridge. (The eventual pair of .256/6.35mm alternates are based on the .25 Remington case.)
August: A supplemental Infantry Board trial is held using AR-15 rifles with modifications based on the earlier Fort Benning and Aberdeen trials.
September: CONARC releases the final report of the Infantry Board's tests: "Evaluation of Small Caliber High Velocity (SCHV) Rifles." The AR-15 is judged to be superior to the M14 and the Winchester LWMR. However, both SCHV candidates are faulted on their burst barrels during rain testing, among other issues. Still, the report recommends that both manufactures be allowed to submit 16 rifles each for further testing by the Infantry Board and the Arctic Test Board.
December: The Army's Combat Development Experimentation Center (CDEC) begins mock combat trials of the AR-15, Winchester LWMR, and the M14. Conducted at Fort Ord, California, the tests cover the effects of the new weapons on squad tactics and organization.
1959....
May: The final report of the CDEC trials, "Rifle Squad Armed with a Lightweight High-Velocity Rifle," is released. It projects that a 5-7 man squad armed with AR-15 rifles would have a higher number of hits and kills than the then current 11 man squad armed with M14 rifles. The report particularly praises the reliability of the tested AR-15 rifles, and suggests that a SCHV design such as the AR-15 or LWMR should be further developed as a replacement for the M14.
1960....
September: Dr. Carten is ordered to provide testing of the Colt AR-15 for the USAF. Ironically, the testing is requested to coincide with Ordnance testing of Dutch-production AR-10 rifles. Moreover, General LeMay and other high ranking officers from the USAF and Army will be in attendance for part of the testing.
November: Ordnance releases the Aberdeen D&PS test results on the AR-10 and AR-15 in separate reports. Once again, Laurence Moore's recommendations and conclusions are missing. However, the remaining data is encouraging. For instance, the Colt AR-15 displays a malfunction rate of 2.5/1000 rounds (less than half of the 1958 Fort Benning tests).
1961...
USAF testing at Lackland AFB continues, pitting the Colt AR-15 versus the M2 Carbine and the M14 rifle. 43% of the AR-15 users score "Expert" in marksmanship qualifications versus 22% of the M14 users. General LeMay requests authority to purchase 80,000 rifles over several years to begin replacement of the M2 Carbine.
1962....
February: Project AGILE begins operational testing of the AR-15 in Vietnam.
May: The USAF's third request for the procurement of 8,500 AR-15 rifles is approved. The rifle and its cartridge are officially adopted for USAF issue. The USAF also plays with prototypes of what becomes known as the M7 Bayonet.
July: Operational testing of the AR-15 in Vietnam ends. ARPA releases "Test of ArmaLite Rifle, AR-15, Report of Task 13A." The report concludes that the AR-15 is superior to the M2 Carbine, and better suited for Vietnamese soldiers than the M1 Garand, the M1918 BAR, and the Thompson SMG. Vietnamese troops and their US advisors reportedly considered the AR-15 "the best 'all around' shoulder weapon" then in use. The report also includes graphic details of the .223 Remington's terminal effects. The results are typically described as "explosive." ARPA recommends that the AR-15 be adopted as the basic weapon for all South Vietnamese forces.
Summer: The commander of the US advisor group in Vietnam requests 20,000 AR-15 rifles for implementation of the Project AGILE recommendations.
The US Navy orders a small quantity of AR-15 rifles for use by its SEAL teams.
September: The Systems Analysis Directorate of the Office of the Secretary of Defense (OSD) finishes a history of intermediate service rifle cartridges and related theory from the .276 Pedersen up to the current AR-15. Known as the Hitch Report (named for Charles Hitch, OSD Comptroller), the study concludes that the AR-15 is superior to the M14 and AK-47. AR-15 equipped squads are theoretically credited with the potential to inflict up to five times more enemy causalities to those issued the M14. The AR-15 is also credited with being more reliable and durable than the M14. The report further suggests that the M14 is inferior to the AK-47 and even the M1 Garand.
October: Pressured by McNamara and Secretary of the Army Cyrus Vance, a series of tactical and technical tests of the relative merits of the M14, AR-15, and AK-47 are ordered by General Earl Wheeler, Army Chief of Staff. Testing was to be performed at bases in the US, Europe, the Caribbean, and the Arctic.
November: President Kennedy is also briefed on the Hitch Report. General Wheeler is given a deadline of January 31, 1963.
1963...
January: Aberdeen's Human Engineering Laboratory releases the report "Summary of Studies Conducted with the AR-15."
General Wheeler reports "The AR-15 is not now acceptable for the Army for universal use." Supporting arguments included that adoption of the .223 Remington cartridge would violate NATO standardization, that the M14 was superior at ranges over 400m, and that the AR-15 design was not completely debugged or reliable. In the trials, the AR-15 suffered a malfunction rate 8 times higher than that of the control M14 rifles. In addition, testing at Aberdeen and Edgewood Arsenal could not duplicate the terminal results reported by ARPA's Project AGILE.
Secretary Vance orders the Inspector General of the Army to review the Army's conduct of the testing. Some questionable decisions and outright skullduggery surfaced. For instance, the AR-15 was judged against M1 Garand-era requirements such as aimed fire out to 800m. The AR-15 rifles were required to fire full automatic, while the M14 rifles were allowed to remain on semi-auto. For comparison testing, the Infantry Board even brought out prototype match rifles and squad automatic versions of the M14 such as the M14(USAIB) (AKA: the M14E2 or M14A1). Most damning was a quote from an Infantry Board memorandum:
"The US Army Infantry Board will conduct only those tests that will reflect adversely on the AR-15..."
Admittedly, some of the AR-15's problems in testing were real, the result of rushed production of the rifles and their ammunition for the rifle trials. The biggest problem experienced was primers blown out of the case upon firing.
In a report to the OSD, Secretary Vance recommends the following: 1) Procure enough rifles converted to the M14(USAIB) standard for issue as automatic rifles to all infantry squads; 2) Procure 50,000-100,00 AR-15 for issue to Air Assault, Airborne, and Special Forces units; 3) Production of standard M14 rifles is to be reduced; and 4) The SPIW program will be scheduled to provide a "follow-on" replacement for the M14 by the end of Fiscal Year 1965. In response, McNamara announces the cancellation of M14 production, with existing contracts to end by the Fall of 1963. A "one-time" purchase of 85,000 AR-15 rifles for the Army is proposed. It is intended as a stopgap measure until the SPIW is ready for fielding.
The USAF type-classifies the .223 Remington as "Cartridge, 5.64 Millimeter Ball MLU-26/P." It also releases the report "Exterior Ballistics of the AR-15 Rifle." The results of cold chamber testing at Eglin Air Force Base indicate that the ammunition cannot meet accuracy requirements in subzero temperatures. A change in the rate of twist from 1-in-14" to 1-in-12" is noted as solving the problem.
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