The 5.56 X 45mm “Timeline” – 1974

A Chronology of Development by Daniel E. Watters



Singapore completes a sale of 10,000 M16S to the Philippines without US approval.

In light of the levels of South Korean ammunition production not being able to keep up with Korean M16 production, the Department of the Army and JUSMAG-K arrange for shipment of 5.56mm ammunition from the US. By the end of the year, 25 million rounds have been delivered to the Korean and 15 million are in transit. Increased amounts of raw material are also provided through FMS to support the acceleration of Korean ammunition production.

The DOD transfers at least $5.7 million in M16 rifles and other non-excess equipment to Thailand as Excess Defense Articles. This leads to Congressional interest and GAO investigations.

The US provides a military assistance grant of 5,435 M16A1 and 63 M203 to South Vietnam.

The US provides a military assistance grant of 2,527 M16A1 to Cambodia.

The US provides a military assistance grant of 4,800 M16A1 to Laos.

The US makes a Foreign Military Sale (FMS) of 470 M16A1 to Chile. Chile separately purchases an additional 5,500 rifles.

The US makes a FMS of 4,500 M16A1 to Jordan.

Haiti purchases ~500 M16A1 from Colt.

Lake City begins production of M193 Ball using GMCS jackets. These are later discontinued the same time as the GMCS jacket M196.

The US Army also experiments with thin walled steel cartridge cases as an alternative to aluminum cases.

The NRA High Power Rifle Committee eliminates the caliber restriction for NRA Match Rifles in High Power Rule 3.1. The NRA Board of Directors later approves the M16 and civilian AR-15 for Service Rifle matches.

Whittaker Corporation’s Shock Hydrodynamics Division and Frankford Arsenal publish “Vulnerability of Small Caliber Caseless Ammunition to Accidental Ignition.”

The Soviet Union adopts the AK-74 rifle and its 5.45x39mm cartridge. This cartridge uses a smaller diameter case than the .220 Russian, but has a slightly larger head than the 5.56x45mm.

Dr. Louis Palmisano and Ferris Pindell begin work on modified variants of the .220 Russian, creating the .22 PPC and 6mm PPC. (PPC: Pindell-Palmisano Cartridge)

Sterling Armament Company of Dagenham, England purchases the production rights to the AR-18 from ArmaLite. Further development is reportedly stopped for a 5.56mm rifle designed by Frank Waters, Sterling’s chief designer.

FN introduces Ernest Vervier’s final design project, the Minimi LMG. While a pair of prototypes were assembled in 7.62mm NATO, further prototypes are constructed in 5.56mm.

Beretta introduces a carbine variant of the AR70: the SCS70.

SIG introduces the SG540 rifle. A more conventional design using a gas operated rotary bolt action, SG540 spawns a family of weapons. To circumvent Swiss export laws, the production rights are licensed off to Manurhin of France. Manurhin does make several sales to former French colonies, but their biggest coup is a stopgap sale to the French Foreign Legion to tide them over until the FAMAS is ready for issue. SG540-series production is later licensed to INDEP of Portugal and FAMAE of Chile.

The British Feasibility Study indicates that the 4.85mm ammunition exceeds the IW‘s 300 meter effective range requirement while just barely meeting the LSW‘s 600m requirement. The LSW also has a limited sustained fire capability that could only be corrected by replacement with a belt-fed weapon. (However, this would violate GST 3518’s goal for a common magazine.) Burst control and full-automatic fire capabilities are deemed unnecessary. On the positive side, the prototype SUSAT works well. Despite the mostly negative results, GST 3518 is formalized as a General Staff Requirement (GSR 3518). The IW is intended to replace the L1A1 SLR and the L2A3 SMG (Sterling), while the LSW is to replace the L4A4 LMG (Bren) and the L7A2 GPMG.

The West German government selects HK to officially continue with caseless ammunition and weapon research.

MAS completes 29 A4 prototypes of the FAMAS.

The Greek Powder & Cartridge Company experiments with a 5.56x49mm cartridge.

Aberdeen’s BRL publishes the report “The Flow Field About the Muzzle of an 6 Rifle.”

South Korea begins production of the M16A1 at Pusan Arsenal. 90,000 rifles are completed by the end of the year.

COMUSKOREA submits a proposal for South Korean FMS credits. He requests $3 million to support M16 production and $2.2 million for expansion of the ROK arsenal.

The Army Electronics Command publishes the report “Laser Aiming Light.” A laser aiming light (LAL ) for use with small arms was developed and field tested. The aiming light was designed with advanced state-of-the-art components consisting of a room temperature laser diode, low impedance laser diode mount, and microelectronic pulser. The LAL has an emission wavelength ranging from 820 to 850 nanometers for use with night vision goggles, is considered to be eye-safe. The LAL housing is 6.25 inches long, 0.78 inch diameter, with a 1.20-inch-diameter lens compartment, and weighs 7.87 ounces. Powered by an 11.2-volt battery, the average optical output power ranges from 50 to 350 microwatts. The aiming light has a boresight mechanism that interfaces with the rifle adapter. The LAL was field tested on the M16 rifle in the single as well as rapid-fire mode and did not exhibit degradation.

Rodman Laboratory publishes the report “M7 Bayonet Handgrip, Reversible Handgrip for Bayonet-Knife: M7.” As the title indicates, the report contains the design of a reversible handgrip for the Bayonet-Knife: M7. The reversible handgrip design can be used on either the right or left hand side of the bayonet handle. The present grip design for all current bayonet-knives consists of a separate design for right and left handgrips. It is recommended that bayonet-knives designed in the future consider the reversible grip design.

Paul Tellie files an US patent application for the FAMAS’ breechface.

GE‘s Richard S. Rose and Burton P. Clark receive US Patent #3,788,191 titled “Burst Firing, Single Barrel, Armament.”

Colt’s George Curtis and Henry Tatro receive US Patent #3,791,256 titled “Machine Gun.”

Andrew J. Grandy files five additional patent applications for a “folded path” cartridge and weapon system.

The US State Department approves the requested multi-year FMS credits for Philippines M16 co production. In a message to the US Embassy, the State Department notes that the $6.922 million for FY 1975 is subject to sufficient New Obligational Authority (NOA) appropriations for FMS by Congress. They also emphasize that the Philippines will have to provide the balance of the funds needed.

Aberdeen publishes the report “Product Improvement Test of 5.56-MM Steel-Cased Ammunition.”

CETME‘s Dr. Günther Voss files an US patent application for the design of an improved Löffelspitz. This version uses two asymmetrically shaped recesses in the bullet’s ogive.

AMARC publishes its final report. Among its recommendations is the creation of a new Armaments Development Center (ADC) at a single location. This should be accomplished through an evolutionary process by consolidating selected elements of Frankford, Picatinny, Rock Island, and Watervliet Arsenal RD&E activities together with the BRL and portions of ARMCOM‘s RD&E Directorate. Edgewood Arsenal’s missions should be incorporated without relocation. A minimum of essential engineering functions should be retained at other arsenals to support required production activities.

AMC Commander General Henry A. Miley, Jr. creates an ad-hoc committee to study the AMARC recommendation for an Armaments Development Center.

The US signs a Memorandum of Understanding with the Republic of the Philippines to establish a M16 rifle assembly and manufacturing capability. Under this agreement, the US will provide a maximum of $15.6 million in FMS credits or in loan guarantees. In the years preceding this, the Philippine government has received ~4,000 M16A1 through FMS.

The testing of FPW candidates results in the decision to continue development of an M16A1-based weapon. Other contenders were the .45 ACP M3A1 SMG and a modified 5.56mm HK 33 known as the MICV. (The latter is a forerunner to the compact HK 53.) The original Rock Island design is later passed on to the US Army Armament Research and Development Command (ARRADCOM) at Picatinny Arsenal for additional work. The prototype FPWs are designated the XM231.

Frankford Arsenal publishes “Model for the Gas Transmission System of the M16A1 Rifle.”

AAI publishes the document “Final Report – Design and Develop a Simplified Serial Fléchette Rifle.” This document covers AAI’s contractual progress in development of the “XM70 Simplified Serial Fléchette Rifle.” Oddly, instead of removing the burst device as Aberdeen’s BRL had suggested earlier, AAI has instead eliminated the full automatic option.

HK‘s Tilo Möller files an US patent application for the design of the G11.

Paul Tellie files multiple US patent applications for the FAMAS’ bolt, locking piece, sights, safety, selector switch, lockwork, the twin ejection ports with its cheekpiece/port cover, bipod, and stock.

Jean-Claude Marie Minaire separately files another US patent application for the FAMAS’ bolt and locking piece.

Aberdeen publishes the report “Product Improvement Test of 5.56-MM Cartridge Case with Optimized Hardness Gradient.”

The US Army Land Warfare Lab publishes the report “Plastic 5.56mm Blank Cartridge.” An expendable plastic 5.56mm blank cartridge for the M16A1 rifle has been developed and tested successfully. The prototype cartridge cases were molded in a 4-cavity production-type mold to insure that the tested cartridges would be producible in quantity without sacrificing quality. This cartridge performs satisfactorily in the semiautomatic mode of fire and operates the rifle reliably in the fully automatic mode when using the standard blank firing attachment (0.063-inch orifice). This blank cartridge will outperform the M200 blank cartridge in feeding and equals its other performance characteristics. Unfortunately, when the Land Warfare Laboratory is closed at the end of the very same month, AAI’s plastic blank cartridge design dies with it.

Aberdeen’s Land Warfare Lab publishes the report “Knife Cutter-Bayonet.” The task was to design and develop a knife cutter-bayonet which could be used as a fighting and survival knife, a bayonet, a wire cutter and a general purpose tool. Requirements such as light weight, an ability to cut both barbed wire and barbed tape and compatibility with the standard Army M16 rifle were essential. Additional features suggested included a built-in saw, a screwdriver, and a sharpening stone. Development was terminated when it was concluded that it was beyond the current state of the art to develop a single item encompassing all the features stated as essential. The report recommends that the US Army continue to issue and use the bayonet and the wire cutter as separate items.

Rock Island Arsenal tests an ARES FARC-2 prototype. Over 4,000 5.56mm rounds are fired. The results lead to a pair of improved prototypes designated as the FARC-3.

WAC recruits begin a sixteen hour basic rifle familiarization course on the M16A1 rifle. (Rifle familiarization had been discontinued for WAC recruits back in 1963 for fear that the women could not handle the M14 rifle.) All trainees attend and participate in the M16A1 weapons training classes; however, firing the weapon is voluntary. Over 90 percent of the women opt to fire the rifles.

At Rock Island, Laurence F. Moore submits a proposal “Engineering Test of Small Caliber Rifle-Ammunition Systems.” Moore suggests that technical arguments do not support the assertion that the variation in ballistic performance associated with the location of the air space in standard rifle cartridges is critically important.

The SAWS Directorate at Rodman Laboratory publishes “Gun, Machine; 6.00mm, XM235,” a Preliminary Operators and Organizational Maintenance Manual.

South Korea requests permission from the US to sell 1,500 to 2,000 Korean-production M16 to Morocco. Despite the small number of rifles involved, the US Embassy and COMUSKOREA voice their opposition to the sale. In contrast, the US Embassy in Morocco recommends approving the request.

FN‘s Maurice Bourlet files an US patent application for the Minimi’s belt box design.

Remington begins delivery of prototype XM742 Soft RAG projectiles to Edgewood Arsenal.

The US Army Arctic Test Center is directed to conduct another check test of the M203 under arctic winter conditions.

The military specification for the M203 grenade launcher, MIL-L-45935, is revised to MIL-L-45935A.

The French decide to delay work on the FAMAS for an evaluation of foreign 5.56mm rifles. The HK 33 ultimately wins the French Army trials against the M16 and FN CAL. However, the adoption of a German rifle is not considered to be politically acceptable.

Colt publishes the report “Electrical Discharge Machining (EDM) Gun Barrel Bore and Rifling Feasibility Study.” A 12-month program was conducted to advance the technology of the EDM process to be applicable to the stringent requirements of gun barrel boring and rifling. The type of barrels employed in the test were .220 Swift gun barrel liners and gun barrel blanks. The various materials were selected on the basis of their resistance to withstand the high stress, high temperature, high pressure, high rate of loading, and high erosion rates encountered in high performance gun designs. The materials investigated were iron/nickel base superalloys, cobalt base superalloys, tantalum, columbium, and tungsten refractory alloys. These materials do not lend themselves to traditional types of machining, and an investigation was undertaken to see if advances in the state of the machining art, such as EDM, were capable of the task. The final effort on the program consisted of boring and rifling 18 gun barrel blanks for delivery to Philco-Ford for final fabrication and testing in .220 Swift M60 test barrels. These barrel blanks, however, were out of specification and could not be fabricated into test barrels.

While tendering an apology for the unauthorized sale of M16S to the Philippines, the Singaporean government informs the US Embassy that the Royal Thai Police have requested an additional 25,000 M16S. Colt is reluctant to approve the sale since they have not been paid royalties from the Philippine sale. The US government will not act without a formal request from Colt. Moreover, assurances are needed from Thailand that the rifles will not be transferred to yet another country.

Aberdeen’s HEL publishes the report “Determining Human Performance Reliability with Infantry Weapons.” This report describes an experiment to measure the extent and consequence of human error in the operation and maintenance of the Stoner 63 rifle and machinegun. Human error rates were related to hardware components, and procedures are explained for modifying otherwise inflated “system reliability” forecasts.

The Human Engineering Labs at Aberdeen publish the report “Dispersion Versus Cyclic Rate Test of 4.32mm Cartridge.” An adjustable brake compensator was used to control, and minimize, round-to-round dispersion of three round bursts. Two weapons, an M16 and a SPIW, were rebarreled to fire 4.32mm ammunition. The impulse levels during the test were on the order of 0.57 pound-seconds. Only the SPIW was further modified to permit external control of firing rate. Ten subject soldiers fired the M16 from the prone and standing positions at its natural rate, and the SPIW from the standing position at 1500 and 800 rounds per minute (rpm). The mean extreme spread (MES) for the SPIW was 10.1 mils at 1500 rpm and 13.1 mils at 800 rpm. For the M16, the MES was 10.2 mils for the prone position and 14.7 mils for the standing. It is concluded that a tunable brake compensator will reduce dispersion; however, the gain in reduced MES is not proportional to the reduction of impulse levels.

The Human Engineering Labs also pit the sole AAI XM70 Serial Fléchette Rifle (SFR) prototype against a pair of Frankford Arsenal’s early experimental 4.32x45mm XM16E1. The XM70 breaks after six bursts.

Secretary of Defense James R. Schlesinger announces the plan to close Frankford Arsenal.

Colt representatives meet with representatives of the Philippines government and Elisco Tool (Elitool). It is agreed that the Philippines has the right to purchase castings, forgings, and extrusions for manufacture of the M16 from suppliers other than Colt.

The US Army Arctic Test Center begins testing of an improved M203 design. The purpose of the test is to evaluate improvements intended to correct previously reported problems related to guide rails, handgrips, and primer punchouts. The tests are conducted at ambient temperatures varying from -4 F to -64 F in a variety of typical arctic field locations. Testing consists of preoperational inspection, transportability and handling, maintenance evaluation, reliability, and adequacy of corrective actions.

William B. Ruger and Harry H. Sefried, II receive US Patent #3,847,054 titled “Burst Fire Mechanism for Auto-Loading Firearm.”

Rodman Laboratory publishes the report “Thermal Analysis of a Liquid Propellant Automatic Rifle.” This effort was undertaken to determine chamber temperatures as a function of firing schedule for a liquid propellant (L. P. monopropellant NOS-283) gun. The automatic gun analyzed was a 6.0mm designed by the P.S.I. (Pulsepower Systems Incorporated) Company under Contract No. DAA-D05-73-C-0317.

AMC Committee-Armament releases its four volume report on the creation of an Armaments Development Center. The Committee prefers a two-site arrangement with Picatinny as the headquarters with the Large Caliber Systems and Small Caliber Systems Laboratories. Aberdeen would retain the BRL and Chemical Systems Laboratory. An alternative arrangement would locate the headquarters at Aberdeen with the BRL, Small Caliber Systems Laboratory, and Chemical Systems Laboratory, while Picatinny would host the Large Caliber Systems Laboratory. The last of the recommended arrangements would locate the headquarters and all of the laboratories at Aberdeen.

Development Test / Operation Test I ends for the SAW candidates. In addition to the three 6mm SAW prototypes, three 5.56mm LMGs have been tested: a Colt M16 HBAR, the FN Minimi, and the HK 23A1. A standard M16A1 was used as the control. The Colt HBAR didn’t make the cut due to its mere 30 round magazine. The decision to drop the HK 23A1 for safety reasons was particularly controversial. First, the HK entry suffered numerous problems due to the experimental XM287/XM288 cartridges. The lot of IVI ammo used possessed thinner case walls than the usual M193/M196 cartridges. Aberdeen personnel also disassembled the trigger group beyond the limits of factory recommendations. During reassembly, critical parts were bent. HK co-founder and managing director Alex Seidel complained vociferously, to no avail.

Aberdeen publishes the report “Engineer Design Test of 5.56-MM Fabrique Nationale Machine Gun, Model MINIMI.” The purpose of the test was to determine the physical and functional characteristics of the weapon. One weapon was provided and tested with 8,653 rounds of special heavy projectile ammunition. The weapon and ammunition physical characteristics and functioning performance were determined in tests for accuracy and dispersion, endurance, and operability at temperatures of +155 F and -50 F. Maintenance and human factors aspects were evaluated. The weapon and ammunition generally exhibited satisfactory performance during all testing. In those instances where performance was marginal, the problem was either corrected or could be corrected by component design changes.

Aberdeen also publishes the report “Engineer Design Test of 5.56-MM Heckler and Koch Machine Gun, Model 23A1.” The purpose of the test was to determine the physical and functional characteristics of the weapon. A total of 2400 rounds was fired. The weapon was subjected to an initial inspection and safety investigation, an accuracy and dispersion test at 100- and 300-meter ranges, an endurance test, and maintenance and human factors evaluations. The evaluations were terminated prior to completion of the endurance test due to the frequent occurrence of feeding failures, and for safety reasons. Firing of the weapon produced severe case-head swelling and ejection of the primer from the case. The testing of the weapon in a high- and low-temperature environment, originally scheduled after the endurance test, also was cancelled. The cause of the weapon-related malfunctions and cartridge-case casualties was not determined prior to test termination.

The US Ambassador to South Korea informs Korean Prime Minister Kim Jong Pil that the US has declined approval for the sale of Korean-made M16 to Morocco.

Colt’s Stanley Silsby and Henry Tatro file a patent application for a hydraulic buffer assembly for the AR-15/M16 family.

Rodman Laboratory publishes “Bore Erosion Gage Calibration Test for M16A1 5.56mm Rifle Barrels with Chrome Lined Bore.”

Rock Island Arsenal publishes “Application of Lubricating Composites to the M16A1 Rifle.” A firing test made on a single M16A1 rifle indicates that a combination of self-lubricating composites applied to the bolt carrier group and a solid-film lubricant coating applied to the upper receiver could reduce malfunctions and maintenance time as compared with conventional lubrication.

Frankford Arsenal publishes the report “An Analysis to Determine the Feasibility of a Non-Luminous Pyrotechnic Fumer.” Results of a mathematical analysis of the thermal radiation emitted from pyrotechnic compositions indicate that non-luminous, base drag-reducing fumers are not feasible. Cartridges from 5.56mm to 30mm were used for testing. The major conclusion reached is that no developmental effort on non-luminous, pyrotechnic fumer ammunition should be initiated.

The USAIB publishes “Development Test II (Service Phase) of Night Vision Sight, Individual Served Weapons, AN/PVS-4.” The AN/PVS-4 is a portable, battery-operated, electro-optical instrument used for observation and aimed fire of weapons at night. It uses the low light level illumination of the night sky (i.e., starlight, moonlight) reflected from the object and its background to form an erect, clearly defined image. The sight can be mounted on the M14 and M16A1 rifles, M60 machine gun, M67 recoilless rifle, M72A1/A2 rocket launcher, and M79 and M203 grenade launchers.

Andrew J. Grandy receives US Patent #3,857,339 titled “Ammunition and Weapon Systems.”

Abe Flatau publishes “Feasibility Study of the 2.5 inch Ring Airfoil Grenade (RAG): A Review and Summary.”

(Next: 5.56mm 1975)

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.


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