The 5.56 X 45mm “Timeline” – 1981

A Chronology of Development by Daniel E. Watters



With the approval of a joint service Rifle Product Improvement Program, fifty experimental M16A1(PIP) are ordered for testing. These rifles are later designated M16A1E1. These rifles include requested improvements such the 3 round burst mechanism, strengthened materials for the butt stock and forearm, a longer buttstock, the improved round/symmetrical forearm, a tapered slip ring for retaining the forearm pieces, a heavy profile barrel with a 1 in 7″ twist suitable for XM855 and XM856 cartridges, and a fully adjustable 800m rear sight. Ironically, Colt had developed many of these improvements during the 1960s and ’70s.

The US provides 11,868 M16A1 to El Salvador as part of a military assistance package. Deliveries stretch through 1982.

The US provides 6.058 M16A1 to Thailand as part of a military assistance package.

The US makes a FMS of 743 M16A1 to Fiji.

Lesotho orders M16A1 and Model 653 carbines.

Qatar begins purchase of 6,000 M16A1 and Model 653 carbines. Deliveries continue through 1983.

Italy receives SCAMP machinery.

L. James Sullivan moves to Italy to work on the ARMi rifle project for Beretta.

HK introduces their G41. It is roughly a HK 33 variant redesigned for compliance with various NATO standards. HK also introduces the product improved HK 13E and HK 23E.

The CETME Ameli is introduced. (Ameli is short for Ametralladora Ligera, which translates to Light Machine Gun.) Designed by CETME director Col. Jose Maria Jimenez Alfaro, the Ameli resembles a scaled down version of the German MG42.

The Swiss conduct troop trials with the SIG SG541 and the W+F SG C42. The 6.45x48mm cartridge is no longer in consideration.

Indonesia adopts the FN FNC. They opt for domestic production of the rifle.

Australia acquires ~100 M203 from Colt.

The US provides 208 M203 to Lebanon as part of a military assistance package.

JSSAP publishes “JSSAP Combat Rifle Study.” For the short term, JSSAP recommends staying on the course of the Rifle Product Improvement Program, which was already beginning to take shape. For the long term, JSSAP recommends that the technology base should be developed in areas such as salvo weapons, caseless ammunition, and advanced optics. Truly revolutionary improvements would have to wait until the year 2000 and beyond.

Thermold Design & Development, Inc. submits “Final Progress Report on Contract DAAK10-79-C-0403.” Thermold was under contract to ARRADCOM to study the feasibility of designing and making a spring that would lie inert for a long period, in a relaxed mode, in a preloaded rifle magazine, with the capability of being instantly tensioned upon need. This was based on Daniel D. Musgrave’s US Patent #3,964,199. Thermold deems it impossible to make the concept of Musgrave’s patent function properly in the standard issue 30 round magazine.

The US Army awards a $2,079,000 contract modification to Colt related to the M203. This is for FMS.

The US Army awards a $100,000 contract to Colt related to the M16 for RDT&E.

Phase A of British Ordnance Board Trials begins for the XL70E3 IW (Left-hand: XL78E1) and XL73E2 LSW. These models are improved versions of the so-called “Production Rifles” with the exception of being chambered for 5.56mm. However, these are barreled for original M193-specification ammo, not the new SS109 NATO standard. In addition, the gas system is revamped, the extractor has been redesigned, and the tungsten inertia pellet has been deleted from the bolt carrier. The latter change was forced by the decision to add a third guide rod to the recoil spring assembly. While it has been decided to ignore the left-hand variant of the LSW, both open-bolt and closed bolt variants of the LSW are now available.

Pier C. Beretta files another US patent application for the adjustable bipod legs used by the AR70/78 LMG.

HK‘s Dieter Ketterer, Horst Jakubaschk, and Emil Rommel file an US patent application for the G11’s rotating breech.

The USMC awards $49,000 and $12,000 contracts to Colt related to the M16.

The Swedes adopt the FNC as the Ak5. Domestic production of the rifle is given to FFV Ordnance (later absorbed as part of Bofors).

FMAP-DM completes development work for their 5.56mm rifle.

Aberdeen publishes the report “Technical Feasibility Test of German 5.56-MM Plastic Training Ammunition.”

Aberdeen publishes the report “Renovation Test of Reloaded 5.56-MM Cartridges.”

The US Army awards a $22,000 contract modification to Colt related to the 1967 Licensing Agreement.

Testing of the improved XM249E1, along with US-manufactured XM855 and XM856, begins at Aberdeen.

Trainees at Fort Leonard Wood use one of the first lots of reloaded 5.56mm ammo. A second lot has to be pulled and salvaged due to poor case annealing. Lake City was responsible for the remanufacturing of the two lots.

The US Army Mobility Equipment Research and Development Command publishes “Integral Color Anodizing of Aluminum Alloy 7075-T6 Upper Receivers of the M16A1 Rifle.” An investigation to determine the suitability of integral color anodizing (ICA) for application to upper and lower receivers of the M16A rifle is described. Report includes details of laboratory tests comparing conventional hard anodizing with various ICA processes. A description of the results of a field test of treated receivers is also described.

Frank E. Waters, on behalf of CIS, receives US Patent #4,272,902 titled “Fire-Arms.”

The US Army awards $61,000 and $4,206,000 delivery orders to Colt related to the M203. The second is for FMS.

US officials raise concerns over potential problems associated with the pending transfer of Pusan Arsenal to Daewoo, including unauthorized M16 rifle exports.

The British ITDU draws up a trials plan for testing of the IW/LSW. In addition, they investigate alternate secondary sights for the weapon.

L. James Sullivan, on behalf of CIS, files an US patent application for the buffered sear of the Ultimax 100.

L. James Sullivan and Robert L. Waterfield, on behalf of CIS, file an US patent application for the drum magazine of the Ultimax 100.

The military specification for the M231 FPW, MIL-S-63348(AR), is revised to MIL-S-63348A(AR).

Colt’s Henry Tatro files a patent application for an open bolt firing mechanism for a new M16-LMG which is under development. (This is the same LMG design which has its rear sight design borrowed for use with the M16A1E1.)

Development tests of the improved HK G11 begin at the Meppen Proving Ground in West Germany.

The US Army awards a $71,000 contract modification to Colt related to the 1967 Licensing Agreement.

With manned firing clearance given as a result of the Ordnance Board Trials, the ITDU begins User Trials of the XL70E3 IW.

Pier C. Beretta receives US Patent #4,288,939 titled “Adjustable Legs Support for Automatic Weapons.”

The US Army awards a $447,000 contract to Colt related to the M203. The US Army also awards $22,000 and $1,451,000 delivery orders related to the M203. The second is for FMS.

The US Army awards a $98,000 delivery order to Colt related to the M16.

The US Army awards a $119,000 contract modification to Colt related to the 1967 Licensing Agreement.

Colt delivers fifty M16A1E1 for testing.

A draft Memorandum of Agreement (MOA) between the US DOD and West German Ministry of Defense is circulated regarding the sharing of caseless ammunition technology.

The US Army awards a $1,147,000 delivery order to Colt related to the M203. This is for FMS.

As the lead service for the program, the USMC Firepower Division at Quantico conducts a “Modified Operational Test” pitting 30 M16A1E1 rifles against 30 standard M16A1. Twenty Marines and 10 troopers from the US Army’s 197th Infantry Brigade participate.

Aberdeen’s Materiel Testing Directorate (MTD) begins a technical feasibility test on 10 M16A1E1 and ammunition. The latter includes FN-produced SS109, Lake City-loaded XM855E1(FN) using FN-produced projectiles, and M193. The rifle testing involves inspections, parts interchange, endurance trials, high and low temperatures, sand and dust, mud, lack of lubrication, accuracy/dispersion measurements, cartridge cook-offs, rough handling, position disclosure evaluation, and sustained fire. The test cartridges are subjected to salt fog, high and low temperatures, mud, and cook-off tests. Safety, human factors, logistic supportability, and reliability evaluations will then be conducted using the data collected.

The British ITDU ends User Trials of the XL70E3 IW.

SIG‘s Alois Bernet and Eduard Brodbeck file an US patent application for the sealed bolt handle slot used by the SG541.

(Next: 5.56mm 1982)

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.