The 5.56 X 45mm “Timeline” – 1965

A Chronology of Development by Daniel E. Watters



Colt offers an improved M16 buttstock. The design is ultimately rejected as it lacks a storage compartment for cleaning materials. However, the improved buttstock material is approved for further use.

Colt discovers a problem with its magazine subcontractor’s hard anodizing process.

While considered to be an unfinished design, a total of 27 (or 29, depending upon the reference) AR-18 rifles are ordered for the SAWS program.

Prototypes of the HK 33 first appear. H&R imports a small number and manages to have them included in the SAWS program. H&R marks these rifles as the T223.

Nederlandsche Wapen-En Munitiefabriek (NWM) of the Netherlands is granted worldwide manufacturing and sales rights by Cadillac Gage for the Stoner 63 system. Oddly, NWM produces only barrels for the system over its history, and only a handful of weapons are assembled using US-made parts.

Remington introduces a commercial version of the popular wildcat .22-250 cartridge.

At Frankford Arsenal, Andrew J. Grandy develops a “folded path” cartridge as part of a study to create a reduced recoil or even recoiless infantry rifle. By rearranging the position of the powder vis-à-vis the bullet, he ends up with a case that has potentially greater venting area than a conventional cartridge case. The folded cartridge is shorter, and the complete cartridge is fully supported by the gun chamber. Requiring only rearward ejection, the need for an extractor groove is eliminated. It is hoped that these features can lead to simplified gun mechanisms and improved cost effectiveness for rifle-ammunition systems. Plans to develop such a system are shelved due to the urgency of higher priority programs.

The US Army awards a $56,000 contract modification to Colt for an additional 500 M16 for the US Navy. The Army also accepts Value Engineering Proposal #37 regarding the ejection port cover. As a result, the Army deallocates $7,533 from the contract.

Colt receives a Priority 04 MIPR from the US Navy for 50 additional M16 rifles.

Field Manual “FM 23-9 – Rifle, 5.56mm XM16E1” is released.

Aberdeen’s D&PS publishes the report “Comparison Test of Rifle, 5.56-MM, XM16E1.”

Colt’s Foster Sturtevant files a patent application for a rate reducing mechanism for the AR-15 family.

The USAF releases the report “Limited Range Test of the M16 Rifle with Eight Types of Rifle and Hand Grenades.” The following grenades were tested: M21 Hand Grenade with M1A2 Adapter, M30 Hand Grenade with M1A2 Adapter, M31 Rifle Grenade, M34 Hand Grenade with M1A2 Adapter, M22A2 Rifle Grenade, M23 Rifle Grenade, M27 Rifle Grenade, and the M7A1 CN Hand Grenade with M2A1 Adapter. No breakage of component parts of the guns or gun stocks occurred during the tests.

Aberdeen’s BRL publishes “Criteria For Incapacitating Soldiers With Fragments And Fléchettes.” Estimates are presented of the probability that single, random hits with a fléchette, which tumbles within a soldier, will result in the incapacitation of the soldier. Experiments at Edgewood demonstrate that within “ballistic” simulants of the human anatomy (i.e., gelatin or goats) relatively quick tumbling occurs with fléchette at striking velocities greater than 3,000 fps. It is suggested that the weight of the fléchette should not exceed about 13 grains else the tumbling will occur too late after entrance and that only a small portion of the fléchette’s energy will be deposited within the target.

FN produces a 2nd Generation 5.56mm rifle prototype with a 3 round burst mechanism.

Gene Stoner files a patent application for the design of the Stoner 63’s left-hand belt box and hanger.

US Army Vice Chief of Staff General Creighton W. Abrams, Jr. approves the new 35 month development program for the SPIW. While sufficient funds are available for FY 1965, LTC Yount believes that a Program Change Proposal (PCP) may be required for FY 1966.

The US Army awards a $5,600 contract modification to Colt for an additional 50 M16. These are the rifles requested by the US Navy the month before. The Army also adds $4,972.80 for replacement upper receivers and bolt assist assemblies.

Colt representatives commence a series of visits and letter exchanges with the Army Staff concerning the maintenance of a production base for the XM16E1. Colt’s representatives declare that they believe there is an obligation to maintain an operating production base in view of the previous Army and USAF procurements, and particularly in view of the situation in Southeast Asia. Colt’s representatives note that the production base could be maintained either through direct contracts from the Department of Defense for stated quantities of rifles or through purchase of rifles for use by the Military Assistance Program. They also advise that if they did not have additional government orders by 1 May 1965, production quantity would decrease and unit costs would increase.

TECOM sends out a letter outlining different facilities’ responsibilities for the SAWS program.

CDCRE-E issues a letter titled “US Army Combat Developments Command Experimentation Center Experiment – Small Arms Weapon Systems (SAWS).”

TECOM issues the letter “Engineering and Service Test of Small Arms Weapons Systems (SAWS).”

The TCC requests new sources of powder for the M193 cartridge from DuPont and Hercules. The submitted powders are EX 8208-4 and HPC-11, respectively.

Colt applies for and is granted permission to use 2,160 modified XM16E1 upper receiver forgings for manufacturing M16 rifles.

Arthur Miller, Charles Dorchester, and George Sullivan file a patent application for the design of the AR-18.

Aberdeen’s BRL publishes “A Kinematic Evaluation of the AR-18 Rifle, Cal. 0.223.” Two AR-18 rifles were fired to obtain a kinematic evaluation of the weapon. A comparison in functioning of a lubricated and an unlubricated rifle was also made. It is found that functioning of the AR-18 rifle varies from lot-to-lot of ammunition. In view of the results obtained in the kinematic study, it is concluded that the basic design of the AR-18 rifle is good. However, because of the neglect in providing a positive feeding system and positive locking devices for some of the subassemblies, the weapon in its present state of design is unsatisfactory, and in some conditions, is unsafe. The authors conclude that the rifle is in an unfinished state of design, but could become both satisfactory and safe without major revisions.

Ernest Vervier, father of the FN MAG58, determines that while the 5.56mm Mini-FAL is satisfactory, a stamped receiver, rotary bolt replacement for the FAL would be more successful in terms of future sales.

Whirlpool Corp. publishes “Design and Development of New and Improved Flechettes and Applicable Weapon Systems.”

The CRDL publishes “Antipersonnel Evaluation of Aircraft Armament Type 6087-010036 Flechettes.”

A letter contract is awarded to AAI for continuance of SPIW development work. AAI and Springfield Armory are to submit ten “second generation” prototypes apiece for a rerunning of the SPIW Phase I evaluation process. The US Army has expressed displeasure with the unconventional layout of the designs, from the Springfield bullpup to AAI’s use of an inline stock with a pistol grip. It is decided that the next generation of SPIW should have a “conventional” stock design like the M14. SPIW ammunition development continues at Frankford and Picatinny Arsenals.

The CDC issues “Combat Developments Directive: Army Small Arms Weapons Systems Program (SAWS).” The CDC assigns overall responsibility for conduct of the study to the Combat Developments Command Infantry Agency (CDCIA).

The CDCIA distributes tasks as follows:

  1. Engineering and Service Tests: TECOM
  2. Troop Tests: CONARC; United States Army, Europe; United States Army, Pacific; United States Army, Southern Command; and United States Army, Alaska
  3. Field Experimentation: CDCEC
  4. Computer Simulation of SAWS: Combined Arms Research Office (CARO)
  5. Weapon Systems Data: BRL
  6. Procurement and Cost Data: WECOM.

CDC issues a directive titled “Army Small Arms Weapon Systems Program (SAWS).”

The CDCIA publishes “Characteristics and Standards Against Which to Conduct Engineering/Service Type Tests for Small Arms Weapons (SAWS) Program.”

WECOM reports to the Boston Army Procurement District that based upon a quality verification visit to Colt in February, the contractor is now considered to be in full compliance with the Quality Control provisions of the contract.

DCSLOG LTG Lincoln submits the memo “Production Base Plan for the M16 Rifle.” The Army’s response to Colt is that the prospects were poor for any new orders for rifles in the near future; however, the Army is not aware of the USAF‘s plans.

At the end of the month, Colt receives their last batch of CR 8136 loaded ammunition for use in rifle acceptance testing.

Frankford Arsenal submits the memo “Request for Deviation Approval or Technical Action (RTA) CHPD 105-65(DV)–Cartridge, 5.56mm, Ball, M193.” In response, Frankford Arsenal has conducted tests to study the effects of bullet obliquity on ultimate function. The results of this test indicate that the bullet obliquity does not adversely affect cartridge performance, but to minimize user reaction, it is recommended that the use of these cartridges be limited to the Continental United States. Frankford Arsenal also recommends immediate process and inspection improvements be taken on the part of Federal.

The 173rd Airborne Division becomes the first US Army unit to deploy to Vietnam with XM16E1 rifles.

XM16E1 training is introduced in Infantry Advanced Individual Training at Fort Gordon for replacement troops headed to Vietnam.

Colt applies for a deviation on the surface finish on the rear face of 600 bolt carriers. Colt also applies for permission to use 3,210 modified XM16E1 upper receiver forgings for manufacturing M16 rifles.

A contract is signed with Colt to provide 30 CGL-4 grenade launchers for ET/ST.

The US Army awards a contract to Remington for FY 1965 Joint Army/USAF M193 requirements. 50 million rounds are purchased at the cost of $47.60 per thousand. This is down from FY 1964’s price of $61 per thousand. (These prices do not include the value of government furnished material.)

On behalf of the US Army, Robert F. Magardo files a patent application for the design of a pump action grenade launcher intended for Springfield’s early SPIW prototype.

FN‘s Vervier follows through on his proposal. The first stamped receiver, rotary bolt prototype is chambered in 7.62mm NATO for direct comparison with the FAL and HK G3. However, Vervier indicates that the lessons learned will be applied to the construction of a new 5.56mm rifle.

The M16 ejector spring is strengthened.

Informal reports of the XM16E1 bolt and bolt carrier seizing begin to surface from Vietnam.

In a letter to Vice Chief of Staff General Abrams titled “Troop Reaction Reports on XM16E1,” General Besson notes that the troops acceptance of the XM16E1 is “almost unanimously favorable,” with no serious problems reported. In a hand-written attachment to the letter, Besson predicts:

“My concern is that individuals becoming familiar with this rifle are going to complain bitterly to home and press when they find themselves in SE Asia with an M14….I think you have a potential flare-up–and I honestly believe the M16 is a better rifle for jungle and rice paddy warfare.”

OACSFOR releases a memo titled “Army Requirements for the M16 Rifle.” It states:

“Prior to the completion of the SAWS project, the Army has no logical or compelling reasons to expand the current basis of issues of the M16 rifle. Such an expansion might in fact be damaging to SAWS in that it could be interpreted as prejudgment of the expected results of the study.”

LTC Yount issues a letter titled “Army Small Arms Weapons Systems (SAWS) Program.”

TECOM issues letters titled “Small Arms Weapons Systems (SAWS) Program.”

Colt is granted permission to use 3,210 modified XM16E1 upper receiver forging for manufacturing M16 rifles. Colt is also granted a deviation on the surface finish on the rear face of 600 bolt carriers.

Marine Corps Landing Force Development Center publishes the report “Stoner 63 Weapons Systems.”

The US Army orders 861 Stoner 63 in multiple configurations for the SAWS program. (These are later named the XM22 rifle, the XM23 carbine, and the XM207 LMG.)

The Stoner 63 system ends Arctic testing.

The Marine Corps Landing Force Development Center (MCLFDC) submits “Stoner 63 Weapon System Final Report” to Marine Corps Headquarters. The Stoner 63 system is recommended for further advanced field testing.

FN produces a 5.56mm prototype constructed from stampings. They have also developed an accompanying grenade launcher.

The BRL publishes “Performance of a Bimetallic Fléchette in Gelatin.”

Chief of Staff General Johnson advises ASA(I&L) Daniel M. Luevano of his decision to make no changes in the Army’s rifle program until the SAWS study is completed, and that the maintenance of an operating line for producing M16 rifles is not necessary.

A week later, General Besson requests approval to procure at least 60,000 XM16E1 rifles for potential Army and military assistance requirements in Southeast Asia. Besson states that although there is no firm requirement at that time to substantiate the proposed procurement, in his opinion it is probable that an urgent demand could develop.

DCSLOG LTG Lincoln replies to General Besson advising him that at present there is no requirement for additional XM16E1 rifles.

During a visit to South Vietnam, General Johnson is besieged by requests from ARVN generals for M16 rifles to equip their own units.

US Air Force Logistics Command sends a letter titled “M16 Rifles,” indicating a requirement of 65,358 M16 rifles per year through the FY 1966-70 time frame. Previous estimates for FY 1966 had indicated a requirement of 36,682 M16. The letter recommends that the US Army use multi-year procurement methods to fill the USAF requirement. AMC General Counsel Barnes makes preparations for renewing negotiations with Colt regarding manufacturing rights and technical data.

William C. Davis is temporarily assigned to Colt as the “XM16E1 Engineering Project Manager.” On Colt’s request, Davis designs the 68 grain GX-6235 projectile. The projectile features a 10-caliber secant ogive. This bullet requires a 1-in-9″ twist; however, it shows excessive fouling when tested in a 1-in-7″ twist barrel.

Charles E. Schindler replaces William C. Davis as Frankford Arsenal’s representative on the TCC.

The US State Department’s Office of Munitions Control approves the export sale of 5,000 AR-15 to the United Kingdom. Many of these rifles will see service with the British SAS in Borneo.

LTC Yount issues letter titled “SAWS Information Letter Number 2.”

The USAIB files its test plan for SAWS testing.

Colt requests permission to parco-lubrite, instead of electrolize, the bolt, ejector, extractor, and extractor pin. This is justified as improving wear resistance and service life of these components.

The US Army awards $54,751.44 to Colt for 54 additional repair part line items.

DuPont completes US Army contract to develop IMR-type powder with greater ballistic stability over a wide temperature range. DuPont’s work with Picatinny had concentrated on 7.62mm NATO, but the resulting IMR 8138M is also suitable for 5.56mm. Unfortunately, the grain size of the powder prevents uniform machine loading of 5.56mm ammunition.

The Colt CGL-4 grenade launcher is officially designated the XM148. The XM148 receives safety certification for ET/ST. The tests are delayed by minor firing pin modifications to eliminate a misfire problem encountered at Aberdeen.

In response to a Springfield RFQ, Winchester proposes an improved version of their earlier SPIW grenade launcher.

Colt’s supply of CR 8136-loaded ammunition runs out. Acceptance testing continues with WC846 loaded cartridges. As result, Colt requests reinstatement of the maximum cyclic rate wavier. The TCC refuses. In response, Colt suspends production of the XM16E1. M16 production for the USAF continues.

LTC Yount broaches the subject of possible future contract options with Colt for additional M16/XM16E1.

AMC General Counsel Kendall M. Barnes reopens negotiations with Colt over TDP and manufacturing rights. Army desires to know whether Colt will still accept the same terms as their October 1964 offer. Colt President Paul A. Benke responds to the negative and presents a new offer with less favorable terms.

Colt’s TCC representative, Mr. Hutchins, requests Government-furnished equipment with which to investigate the reason for the increased cyclic rate.

Colt changes the bolt carrier’s finish from electrolized to a chrome-plated interior and a parco-lubrited exterior.

The US Army approves a change in M16 bolt hardness.

The US Army awards $21,882.84 to Colt for 22 additional repair part line items.

The CDCIA publishes “Systems Constraints for Small Arms Weapons Systems (SAWS) Parametric Design Task.”

The BRL publishes “Relative Electiveness of Conventional Rifles and an Experimental ‘Salvo’ Weapon in Area Fire.”

The BRL also publishes “On the Effectiveness of Various Small Arms Weapons in an Anti-Ambush Role.”

Olin declines to submit a new powder to replace WC846.

In the report “Study of Current Primer-Sensitivity Criteria for 5.56MM Ammunition,” Frankford Arsenal notes that the restrictive primer sensitivity requirements are having the predicted results, causing high rejection rates of primer lots by manufacturers.

Aberdeen’s D&PS publishes the report “Engineering Test of Cartridge, 5.56-MM, Tracer, XM196.” The purpose of the test was to determine the XM196’s physical dimensions, accuracy, tracer performance, cook-off temperature, vibration effects, brush deflection, erosion, penetration (pine board, steel helmet, and armored vest), and gun functioning. It is recommended that the XM196 be considered suitable for use with the M16 and XM16E1 rifles.

FN builds yet another prototype 5.56mm rifle.

AAI publishes “Tracer Study for SPIW Point Fire Ammunition.”

Technik, Inc. publishes “Sabot, Fléchette Investigations.”

On behalf of the US Army, Frederick Reed receives US Patent #3,190,023 titled “Multimagazine, Two-Stage Feeding Device for Firearms.”

Olin-Winchester’s Joseph A. Badali and James H. Johnson file a patent application for the design of their SPIW‘s semi-auto grenade launcher.

Frankford Arsenal orders five XM16E1 fitted with .17 caliber barrels. The experimental 4.32x45mm “Micro-Bullet” cartridge is loaded using Remington formed and primed cases. Two of test rifles include Colt’s 2 round and 3 round burst mechanisms. Two other rifles are not equipped with burst mechanisms, while the final pair is sent to Springfield Armory for testing of micro-bore chrome plating procedures. Exploring use in unmodified XM16E1, 5.56mm cartridges are also loaded with saboted .17 caliber projectiles.

L. James Sullivan leaves Cadillac Gage to join Sturm, Ruger & Co.

Stanley R. Resor is appointed Secretary of the Army.

MACV commander, General Westmoreland asks Army Materiel Command to examine the issues necessary to issue M16/XM16E1 rifles to all US troops in Vietnam.

Soon afterwards, General Westmoreland becomes commander of the newly formed US Army, Vietnam (USARV).

In an informal letter to General Abrams, General Besson suggests that the Army begin thinking about large scale procurements of the M16/XM16E1. He points out that according to the latest projection for commitment of forces equipped with the XM16E1 rifle to Southeast Asia, the CONUS stocks of the rifle will soon be depleted. Besson further points out that the lightweight and rapidfire characteristics of the XM16E1 rifle make it a much better weapon for use in Southeast Asia than the M14 rifle. A note added to this letter states:

“I have just received a TWX from MACV requesting for planning purposes cost and delivery schedule for 50,000 XM16E1 rifles and associated ammunition. In view of this request from Westmoreland, I think the 60,000 figure is too conservative.”

In return, Abrams sends a handwritten memo to ACSFOR LTG Theodore J. Conway.

“The heat’s on! It seems to me that General Besson’s line of reasoning might lead to a US requirement for about 8 division forces worth and an initial ARVN requirement somewhat in excess of 200,000.”

In a letter titled “FY 66 PEMA Program,” General Besson submits a PEMA Reprogram Request to DCSLOG LTG Lincoln for 43,000 XM16E1 rifles at a cost of $5,160,000.

The US Army awards an $112,000 contract modification to Colt for an additional 1,000 M16 for the US Navy.

CDCEC publishes “Outline Plan USACDCEC Experiment 65-4, Small Arms Weapon Systems (SAWS).”

SAWS testing by the USAIB begins at Fort Benning. Test items include the M14, M14E2, M60, XM16E1, CAR-15 SMG, CAR-15 HBAR M1, HK 33, AR-18, and the Stoner 63 rifle, carbine, AR, LMG, and MMG.

The US Army Armor Board receives three Stoner 63 Fixed Machine Guns for testing as coaxial weapons for the M60 tank. Crews are unable to mount the weapons using existing hardware. Given the absence of the Colt CMG-1 Fixed MG, the test parameters are limited to vehicle stowed weapons. Five Stoner 63 Carbines and five Colt CAR-15 SMG are accepted for testing.

Springfield Armory publishes the report “Blank Cartridge and Blank Firing Attachment for 5.56MM M16 (AR-15) Rifle.”

Springfield assembles the first two prototypes of its second generation SPIW.

The CRDL issues the report “Wound Ballistics of the SPIW Fléchette.”

Picatinny Arsenal publishes “Fléchette Design Performance Characteristics and Potential Casualty Rates.”

Frederick Reed receives US Patent #3,196,568 titled “Switching Device for a Tandem-Type Magazine Feeding System.”

Springfield signs a contract with Winchester to design, fabricate, and develop the SPIW grenade launcher.

The 1st Cavalry Division (Airmobile) is issued XM16E1 rifles, completing the Army’s planned issue of XM16E1 rifles.

A SPIW Executive Committee meeting is held at Aberdeen Proving Ground. Springfield is directed to change the Winchester grenade launcher design’s feeding system. A contract change is placed to incorporate the feed system design changes. The committee tentatively decides to continue the development of the AAI semi-automatic grenade launcher. This will depend on the results of current testing.

The US Army awards a $4,182,304 contract modification to Colt for the 36,682 M16 requested by the USAF the month before, plus an additional 660 M16 for the US Coast Guard.

OCSA memorandum “Review of M16 Inquiry of 1962-63” responds to General Johnson’s request that a review be conducted of the Inspector General’s investigation of the AR-15 and M14 comparative evaluation conducted in 1962-63. The review is to provide information on the comparative evaluation and the decision to procure the M14 and M16, the factors leading up to the Inspector General’s investigation, results of the investigation, and significant events subsequent to the investigation which would bear on a decision to procure additional M16 rifles.

M16/XM16E1 contract administration is transferred from the Boston Army Procurement District to the Hartford Defense Contract Administration Services District (DCASD). Requirements established by the existing QALI are maintained. Various quality verification visits are made to Colt; however, no significant actions are taken as a result of these visits.

The US Army and Colt initiate work on a 30 round magazine.

Colt files a RTA for a bolt catch change to prevent battering of the lower receiver.

Frankford Arsenal draws up the specifications for the M232 Dummy cartridge.

The US Army Arctic Test Center publishes the report “Final Report of Service Test of Cartridge, Tracer, 5.56MM, XM196 Under Arctic Winter Conditions.”

The BRL publishes “Terminal Ballistic Evaluation of the XM144 Fléchette, the 5.56-mm, M193 Ball Bullet and the 7.62-mm M80 Ball Bullet.”

Gene Stoner receives US Patent #3,198,076 titled “Convertible Gun.”

CETME‘s Dr. Günther Voss files an US patent application for the design of the Löffelspitz (spoon-nose) projectile.

Springfield signs a contract with another private facility to develop an alternative feed system for the SPIW rifle. Development testing of the rifle is reinitiated.

Springfield’s Alfred L. Montana receives US Patent #3,200,709 titled “Firing Mechanism with Integral Safety.”

The US Army awards a $2,072,481 contract modification for an additional 18,671 M16 for the USAF. Negotiations are in progress for an additional 4,669 M16 to fill the USAF‘s supplemental FY 1966 requirement.

In a letter titled “FY 66 PEMA Program,” DCSLOG LTG Lincoln returns without action General Besson’s request for a PEMA reprogramming action. This is based on a decision by the Chief of Staff not to buy additional XM16E1 rifles at that time to equip units not then authorized the XM16E1.

Colt changes the bolt carrier key’s finish from electrolized to chrome-plate and parco-lubrite.

At Frankford Arsenal, Charles E. Schindler releases a report titled “Fifteenth Memo Report on AR-15 Rifle-Ammunition System: Investigation of Alternate Propellants For Use in 5.56mm Ball and Tracer Ammunition.” DuPont’s EX 8208-4 is shown to have moderate fouling, but records higher gas port pressures than WC846. Hercules HPC-11 shows the least visible fouling, but further examination shows that heavy fouling has constricted the gas tube. The report recommends that EX 8208-4 be approved for use in M193 Ball and M196 tracer cartridges, that CR 8136 and IMR 4475 be withdrawn, and that Hercules and Olin reduce the fouling characteristics of their respective powders. However, unlike WC846, HPC-11 is not approved for current use.

At Colt, William C. Davis finishes evaluation of 5.56mm plastic training cartridges produced by Dynamit Nobel’s Geco.

The BRL publishes “The Drag Coefficient of 5.56-mm, M193, Ball Bullet in Gelatin.”

CDCRE-E issues a letter titled “Outline Plan, Small Arms Weapon Systems (SAWS) Experiment.”

Colt applies for a waiver for an oversized chamfer on 5,200 buttstocks.

The US Army Armor Board begins service testing of the Stoner 63 Carbine and the Colt CAR-15 SMG.

The first contractor-fabricated XM216 SPIW ammunition is delivered. Previous XM216 ammunition had been fabricated solely by Frankford Arsenal.

Colt’s military sales manager, James B. Hall, informs General Westmoreland’s staff that Colt will stop producing XM16E1 rifles in January if no further orders were made.

DCSLOG LTG Lincoln includes in the Omnibus Program Change Proposal the anticipated combat consumption for the XM16E1 and advises AMC that the requirement will be included in the January Supplemental (FY 1966) budget. It is requested that 30,134 XM16E1 rifles be included in the budget to meet anticipated combat consumption for troops in Vietnam at that time.

The US Army awards a $597,396 contract modification to Colt for an additional 5,269 M16 and 100 XM16E1. The order covers the remaining USAF FY 1996 requirement, the recent US Coast Guard request, and replacement of the rifles provided by the Army to Australia. The Army also awards $813,138.47 to Colt for 90 additional repair part line items.

Springfield Armory publishes the report “Water-in-the-bore Investigation.”

Colt applies for and receives a waiver for oxidation at the spot weld on 12,000 bipods. Colt also applies for a waiver for an oversized chamfer on 278 front sights. Colt receives a waiver for an oversized chamfer on 5,200 buttstocks.

The CRDL publishes “Wound Ballistics Evaluation of Caliber .17 Bullets.”

Olin-Winchester’s James H. Johnson and Julius E. Brooks file a patent application for the “soft recoil” mechanism of the Winchester SPIW.

McNamara orders Springfield Armory to prepare for closure by April 1968.

The US Army awards a $2,775 contract modification to Colt for an additional 25 M16 for the US Coast Guard. Two weeks later, the Army awards a $6,660 contract modification for 60 M16.

At Colt, William C. Davis releases the report “Effect of Ammunition Variables on Acceptance Testing of XM16E1 Rifles.” Davis notes that rifles which meet cyclic rate requirements when tested with CR 8136-loaded ammunition will often fail the same requirements when tested with WC846-loaded ammunition. Going further, Davis estimates that none of the rifles are likely to fail cyclic rate testing with CR 8136-loaded cartridges, while more than half of the rifles could be expected to fail when tested with WC846-loaded cartridges. Davis suggests that the maximum acceptable cyclic rate might need to be raised as high as 1,000rpm in order to accommodate acceptance testing with WC846-loaded cartridges. Davis also notes that bolt failures and malfunctions are more likely to occur at higher cyclic rates.

SAWS testing ends at Fort Benning.

CDEC personnel report to the TCC by telephone. CDEC suspects that the higher rate of malfunctions there are seeing vis-à-vis the 1959 test may be the result of higher cyclic rates and excess fouling caused by WC846.

Dr. Wilbur B. Payne, the Chief of Operations Research for the OSA, submits a memorandum to his DOD counterpart expressing his concern over problems being experienced with ammunition loaded with ball powder. Dr. Payne is concerned that the same problems experienced by CDEC during the SAWS trials may also be occurring Vietnam.

Colt applies for and receives a waiver for 360 barrels a point low on the Rockwell C scale in hardness, and a lot of 4,800 rifles which experienced a broken extractor spring at 2,614 rounds during endurance testing. Colt also applies for waivers for 23,500 oversize (internal diameter) hammer springs and the surface finish of 5,000 carrier keys.

At a meeting at WECOM HQ, problems with Frankford Arsenal-produced XM216 ammunition are discussed. There are issues with expanded case heads and primer punch-outs. Frankford quickly changes the thickness of the primer cups to alleviate the latter problem.

Employees at Olin’s East Alton, IL ammunition plant go on strike. The plant is the sole source for Ball Powder and the current manufacturer of M196 Tracer.

General Westmoreland sends an urgent cable to General Johnson requesting 170,000 XM16E1 rifles for US troops in South Vietnam. The next day, Westmoreland bypasses the US Army’s chain of command, and uses USAF communication assets to contact Senator Donald S. Russell (D-SC), Chairman of the Senate Armed Services Committee. Westmoreland requests 170,000 XM16E1 rifles, including 10,000 for immediate use and approximately 10,500 to be equipped with the XM148 grenade launcher. Westmoreland further requests that M16 and XM16E1 rifles now in hands of US forces not engaged in general combat be redistributed against his stated requirement. The ASA(I&L) Dr. Robert A. Brooks directs General Besson to award a letter contract to Colt for the accelerated production and delivery of 100,000 XM16E1 rifles. 68,000 are for the Army and 32,000 for the USMC. Besson is also directed to make plans for the immediate expansion of 5.56mm ammunition production capacity. Colt is told to prepare for production rates of 16,000 rifles per month. (Colt’s current production rate is 8,000 rifles per month.)

A day later, Westmoreland requests 106,000 rifles for ARVN troops and 17,000 rifles for South Korean troops. There is an additional requirement of 5,742 XM148 grenade launchers. McNamara contacts Westmoreland to clarify whether the request of 123,000 rifles for ARVN and ROK troops is part of his original total of 170,000 rifles, or in addition to the original request. Westmoreland revises his original request for US troops to 179,641 rifles.

USMC field commanders in South Vietnam agree with General Westmoreland, and recommend USMC adoption of the XM16E1 to replace the M14 in Vietnam. The decision is ultimately made to procure XM16E1 to equip all USMC forces in the WestPac and CONUS training bases.

Proposed Army-Marine Corps Fiscal Year 1966 Procurement for Free World Forces

Quantity Amount
South Vietnam Army
XM16E1 Rifles 100,000 $14.1 million
5.56mm Ammo 535 million $33.2 million
ROK Army
XM16E1 Rifles 14,000 $2.0 million
5.56mm Ammo 76 million $4.7 million
South Vietnam Marines
XM16E1 Rifles 6,000 $0.9 million
5.56mm Ammo 32.3 million $2.0 million
ROK Marines
XM16E1 Rifles 3,000 $0.5 million
5.56mm Ammo 14.5 million $0.9 million


CINCPAC Admiral Ulysses S. Grant Sharp, Jr. concurs with the proposed FY 1966 MAP Requirement for the XM16E1, and recommends immediate JCS action to meet the requirement.

DCSLOG LTG Lincoln submits a change to the January 1966 Supplemental Budget for 100,000 XM16E1 at a cost of $11 million, and 494.9 million rounds of 5.56mm ammunition at a cost of $30.7 million. The DOD also adds funds for the 123,000 rifles requested for the Military Assistance Program, along with 657.7 million rounds of 5.56mm ammunition.

A communication between the Director of Procurement to ASA(I&L) Dr. Brooks titled “Expansion of Production Capacity for 5.56mm Ammunition” notes that DCSLOG LTG Lincoln recommends that a monthly production capacity of 100 million rounds of 5.56mm ammunition must be established to meet the increased Southeast Asia requirements. In a memo of the same title, Secretary Vance approves LTG Lincoln’s plan to convert .30 caliber ammunition facilities at Lake City Army Ammunition Plan at a cost of $2 million and at Twin Cities Army Ammunition Plant at a cost of $3.5 million.

To alleviate the shortage of rifles for combat units, the USAF offers to provide production M16 rifles (without the manual bolt closure device) to the Army. The Army accepts 3,543 of these rifles from the USAF for issue to Continental United States training bases in order to release those bases’ assets of XM16E1 rifles on hand to MACV.

The US Army awards a $3,996 contract modification to Colt for an additional 36 M16.

The DOD denies clearance for Colt representatives to visit South Vietnam to check on performance of the XM16E1.

Singapore orders a small number of AR-15 and AR-15 HBAR for testing. These are delivered from January to March, 1966.

Michigan Governor George Romney (R) includes containers of Dri-Slide, a moly-disulfide lubricant, in Christmas packages sent to US troops in South Vietnam. This sparks a minor controversy over the suitability of Dri-Slide versus the issue lubricant VV-L-800.

Frankford Arsenal publishes “Report on a Test of Cartridge, 5.56mm Ball, M193, Lots RA5074 and WCC6089 in M16E1 and AR-15 Rifles.” After firing 18,000 rounds each of WC846 and CR 8136-loaded ammunition. Engineers note a significant increase in cyclic rate with WC846. They note that cyclic rate is related to certain malfunctions, and suggest that cyclic rates over 850rpm are more likely to result in malfunctions. Further observations are needed before making definitive conclusions regarding fouling. While heavier fouling was noted with WC846, there were no attributable malfunctions due to the fouling. On the positive side, the function and endurance performance was superior to other standard weapons. The accuracy of the tested ammunition and rifles was also superior to other standard weapons with average quality ammunition. No accuracy differences were seen between the two powder types. They conclude that there is no immediate requirement for remedial action for the existing weapon and ammunition as fielded. However, they would like to isolate the interior ballistics differences between WC846 and CR 8136. This is so that the ammunition specifications could be modified to insure comparable performance with all qualified powder types.

The USAIB publishes the report “Small Arms Weapon Systems (SAWS).” Testing indicates that there are no significant differences between the SAWS weapons except for reliability. The current standard 7.62mm weapons (the M14, M14E2, and M60) are found to be significantly more reliable than their 5.56mm counterpart SAWS candidates (the CAR-15 family, Stoner 63 system, HK 33, and AR-18). Testing also indicates that XM16E1 rifles are more likely to foul, exhibit high cyclic rates, and suffer more malfunctions as a result when using cartridges loaded with WC846 versus CR 8136. The USAIB recommends that none of the 5.56mm weapons (including the XM16E1) be adopted until significant improvements over 7.62mm weapons can be made.

The US Army Armor Board publishes “Service Test of Small Arms Weapons Systems.” Service tests of the Stoner 63 Carbine and the Colt CAR-15 SMG were conducted to test their suitability as vehicular-stowed weapons on combat vehicles for local security purposes and other dismounted action. The Stoner 63 Carbine and the Colt CAR-15 SMG offerd significant advantages over the current standard caliber M3A1 SMG in range, general utility, safety, and handling characteristics for its intended purpose. Except for effective range, the Stoner 63 Carbine and the Colt CAR-15 SMG also offer the same advantages over the M14E1. The Stoner 63 Carbine as tested is suitable for US Army use as a combat vehicle-stowed individual weapon, and the Colt CAR-15 SMG could be suitable when its deficiency is corrected. Both the Stoner 63 Carbine and Colt CAR-15 SMG are safe for their intended use. It is recommended that, subject to action by Department of the Army to adopt 5.56mm weapons on a scale for general use by ground troops, the Stoner 63 Carbine weapon be adopted for US Army use as a vehicle-stowed individual weapon for combat vehicle crew members.

The US Army Aviation Board publishes the report “Limited Service Test of Small Arms Weapons Systems (SAWS) for Use as Individual Weapons by Army Aircraft Crew Members.” The SAWS candidates were tested in ten types of aircraft to determine their suitability for use by aircraft crew members.

The CDCIA publishes “A Method for Evaluating Small Arms Weapons Systems.”

D&PS publishes “Engineering Test of Small Arms Weapons Systems (SAWS): Volume I, Partial Report.”

TECOM issues the letter “Reports of Engineering, Service, and Service- Type Tests of Small Arms Weapons Systems (SAWS).”

Colt receives waivers for 278 front sights with an oversized chamfer, 23,500 oversize (internal diameter) hammer springs, and the surface finish of 5,000 carrier keys. Colt also applies for and receives a waiver for a lot of 4,800 rifles which experienced a broken extractor spring at 2,957 rounds during endurance testing.

On behalf of the US Army, Charles F. Packard receives US Patent #3,225,653 titled “Charging Handle Assembly.”

The military specification for the M232 Dummy Cartridge, MIL-D-60254(MU), is published.

AMC receives a request for 200 ruptured cartridge case extractors. WECOM modifies an existing Springfield Armory design for 7.62mm NATO. A decision is also made to test a commercial device as well. Springfield places an order for 200 ruptured cartridge case extractors from Edward C. Herkner. Later in the month, the order is increased to 250. Ultimately, Herkner is requested to hand deliver the extractors to Springfield. The extractors are then passed on to the AMC so that General Besson can take them with him on his upcoming trip to South Vietnam.

The USMC orders 1,080 Stoner 63 rifles and accessories for use in additional testing.

Springfield has completed fabrication of 11 second-generation SPIW. Seven are for development testing, and four are for delivery to the PMR.

Frankford Arsenal delivers the first XM216 cartridges with the thicker primer cups. The problem with primer punch-outs appears to be solved.

(Next: 5.56mm 1966)

by Daniel E. Watters, Small Arms Historian
Post questions or comments at The 5.56mm Timeline’s Facebook page.

Document History
Publication: 12/10/1998
Last Revised: 05/17/2009


Author’s Note
This article was originally published at The Gun Zone — The Gunperson’s Authoritative Internet Information Resource. My friend and mentor Dean Speir has graciously hosted my articles at TGZ for nearly 16 years. These articles would likely have never appeared online without his constant encouragement and assistance.With TGZ’s closure in early 2017, Dean encouraged me to find a new home for my scholarship so it wouldn’t be lost in the dustbin of the Internet. Loose Rounds has welcomed me with open arms. In the future, I intend to expand my legacy TGZ articles and add new contributions here at Loose Rounds.


Comments are closed.