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Lightweight Small Arms Systems (LSAS)
Lightweight Small Arms Technologies (LSAT)
Lightweight Machine Gun and Ammunition (LMGA)
Lightweight 5.56mm Ammunition (LWA)
Lightweight Family of Weapons and Ammunition

In FY03, the US Army began a program to investigate lightweight weapons and ammunition technologies with the goal of developing a lightweight replacement for the 5.56mm M855 cartridge for use in existing conventional weapons and the XM8 lightweight carbine. At that time a 20 percent or more reduction in ammunition weight was seen as being potentially viable. It was expected that the ammunition would be demonstrated in FY04 and a transition to the System Development and Demonstration Phase in FY05. The program was part of work being done as part of the US Army's Objective Force Warrior (OFW) program.

The program, then referred to as the Lightweight Family of Weapons and Ammunition was seen as a high risk program, dealing with materials properties, propellant volume of the cartridge, and the extraction and ejection cycle of the parent weapons. Conventional weapon design could even require 2 piece cartridge case. Such developments were based on work already being done by industry and at Picatinny Arsenal on polymer and metal-polymer hybrid cartridge cases. Ammunition work had been carried out by Alliant Techsystems, Frontier Performance Polymers Corporation, FN Manufacturing, Inc., Knox Engineering Company, and Veritay Technology, Inc.

One of the initial focuses of the project was the automatic rifleman. The M249 Squad Automatic Weapon (SAW) and its ammunition often constituted over 40 percent of of the combat weight carried by the automatic rifleman. Average combat weight often exceeded 90 pounds. A new lightweight weapon and ammunition were critical. This Lightweight Machine Gun and Ammunition (LMGA), as it became known, was seen as supporting the Army transformation and OFW. It would maintain the lethality and reliability of existing light machine guns and maximize integration with OFW's Lead Technology Integrator for switches, power, aiming, and other accessories. As of FY03, the program was funded through to FY07.

The design of the new weapon was to be a "clean sheet of paper" effort, utilizing either plastic cased or caseless ammunition designs. Specific goals included a 30-35 percent weapon weight reduction, 30-40 percent ammunition weight reduction, 30 percent reduction in ammunition volume, the elimination or redesign of the cartridge links, and a modular design with interchangeable components.

During FY03 and FY04, the various components of the LMGA were studies and demonstrated. System Integration Contracts were awarded in April 2004 and subsequently 2 teams formed to submit designs. AAI served as the prime contractor and systems integrator for a team that also included ARES, Inc, Battelle, Omega Training Group, Inc, and St. Marks Powder (a division of General Dynamics). General Dynamics Armament and Technical Products formed a similar arrangement with General Dynamics Ordnance and Tactical Systems and Knights Armament Company. Further ammunition work was to be done in coordination with the US Army Research and Development Command (ARDEC).

The AAI design achieved the weight reduction objective for both the ammunition and the weapon, utilized a simplified weapon action, and made extensive use of composites. AAI developed the weapon as part of a spiral development approach. A light machine gun and a medium machine gun were proposed. The GDATP design met or exceeded weight reduction objectives, with an emphasis on process to achieve the final product. GDATP utilized a flexible weapon and ammunition design during their development.

As of February 2005, the LMGA efforts, seen as complementing both the Objective Individual Combat Weapon (OICW) and the Objective Crew Served Weapon (OCSW), were expected to offer significantly reduced weight over the existing M249 machine gun and its associated ammunition. The LMGA would lighten the soldier's load, provide improved battlefield mobility and reduced logistics burden to maximize operational utility and survivability, while maintaining or improving existing levels of performance. The Lightweight 5.56mm Ammunition (LWA) effort, which had been completed in FY04, sought to determine the feasibility of replacing 5.56mm ammunition brass cartridge cases with lighter weight materials such as aluminum or polymers.

A 9 month long design phase, phase 1, was subsequently conducted. This involved virtual prototyping of weapons and ammunition. In the end the design concept put forward by AAI was selected in February 2005. ATK jointed the team after AAI's selection to handle development of the ammunition. By May 2005, the project had been renamed as the Lightweight Small Arms Technologies (LSAT). The project had also entered the develop, fabricate and test phase, phase 2. During this phase, it was expected that the program would continue development and fabricate subcomponents, and the subcomponents and ammunition would be tested. System integration planning and preliminary testing would then be conducted. The LSAT design as of 2005 met all program requirements and exceeded many of them as well. The design exceeded weight goals, improved lethality, improved logistical burden, improved weapon ergonomics, and maintained comparable production costs to existing systems.

As part of the LSAT program, new efforts were started to determine the feasibility of a "Company Machine Gun," a weapon with medium machine gun performance in light machine gun package. These efforts were to include an initial study to identify an optimum caliber. Ammunition development as part of the LSAT program had been broken into 2 separate spirals, one for telescoped ammunition and one for caseless ammunition. The telescoped ammunition would consist of a projectile inside a polymer cartridge case, thus reducing overall cat ridge length and weight. Caseless ammunition would consist of a similar design, but with a full combustible cat ridge case. This would remove the need for the weapon to extract spent casings. The telescoped ammunition development represented a lower risk than the caseless ammunition, while still offering a major improvement over traditional cartridges.

By May 2006, 4 more contractors (Johns Hopkins University Applied Physics Laboratory, Veritay Technology, MSC, and Polymer Technologies, Inc.) had been added to the program, and a test weapon (configured to fire telescoped ammunition) had been fabricated. A contractor to handle production of the weapons was to be determined.

The first test weapon, serialed CT1, demonstrated basic functionality in a dynamic test fixture, but as an integrated weapon. The weapon had fired approximately 400 rounds, including during repeatable successful burst fire operation, as of May 2006 and had validated the ADAMS kinematic model. Various issues had been resolved using a combination of modeling and test data, which was to be incorporated into a second test weapon, to be serialed CT2. That weapon was also to utilize an improved version of the telescoped catridge.

The caseless design was still in development, being designed to maximizes commonality with with the CT weapons. A number of features for the caseless variant had been evaluated, including: chamber sealing and lock options, firing pin arrangement, weapon powering approach, and packaging for unique ammunition free volume requirements. Residual caseless ammunition from the Advanced Combat Rifle program, during which the Heckler and Koch G11 had been tested, was used to support early weapon component design evaluations. Test fixtures had completed firing evaluation of chamber sealing concepts for effectiveness and durability. A firing fixture for evaluating caseless ammunition thermal outputs had also been developed.

By May 2007, the original CT1 demonstrator had been converted to the new variant of the telescoped catridge (referred to as Sprial 2), and the CT2 demonstrator had been completed. Integrated weapon fit up and testing was scheduled for June 2007. The weapons had already been fired in additional tests, and had been awarded limited safety releases for manned fire.

In addition, the first of the caseless catridges had also been fabricated (referred to as Sprial 1; both the telescoped and the caseless ammunition had their own separate spirals). The Spiral 1 caseless round was produced using an improved fabrication process over previous caseless designs tested at Picatinny Arsenal, which demonstrated good dimensional control. Ballsitic testing had been conducted using a Mann barrel in order to verify existing modeling data. Modelling and mock up of the caseless weapon was expected to begin soon at that time.

By May 2008, further ammunition developments had been completed. A Spiral 3 telescoped catridge had been developed, and a Spiral 2 caseless catridge had been in testing, with a Spiral 3 variation planned. Demonstration of the weapons configured for telescoped ammunition continued. CT1 had fired approximtely 6,500 rounds, while CT2 had fired approximately 2,000 rounds. Both weapons included various design improvements and refinements. The various weapon system components for the caseless demonstrator were undergoing testing at that time.

In 2008, work on an LSAT rifle design had also been initiated, starting with a requirements analysis. Concept development and tradeoffs had been explored, with the projected outcome being a system with both telescoped and caseless designs like the LSAT LMG. 17 rifle concepts with various mechanisms and overall configurations were evaluated. Two magazine approaches, one weapon powered and one spring powered, both focused on high capacity, were also evaluated. The designs had been downselected to 2 each telescoped and caseless. As of May 2008, a detailed design was nearing completion with full detail 3D models for structural and kinematic analysis. As of May 2009, the LSAT program was also exploring potential medium machine gun and sniper rifle designs.

As of May 2009, a Joint Capability Technology Demonstration was planned for 2011, to demonstrate military utility of lightweight small arms technology. At that time it was on hold pending DA approval. The LSAT program reported that it had recieved positive feedback from the Field Assistance in Science and Technology (FAST) team in Afghanistan after responding to a request for information about the program in April 2009. The suggestion was that if the LSAT program matured to a point where the weapon was viable, US Army units in Afghanistan were prepared to submit Operational Need Statements for the system. The LSAT program was also continuing to generate interest in the program and schedule additional demonstration for interested entities, including the US Special Operations Command and the US Marine Corps.

In March 2010, weapon action testing had begun on the rifle demonstrator designed to fire telescoped ammunition. The design was an aft feed, rising chamber design with the same overall weight and length as an M4 carbine, but with a barrel 4 inches longer. The weapon was 24.75 inches with buttstock folded and featured a 42 round magazine. As basic design for a caseless rifle was also available by May 2010. In addition, at that time, a third LMG design, serial CT3, had been developed. The weapon's weight was reduced to 9.21 pounds (the CT1 weighed 9.97 pounds and the CT2 weighed 9.81 pounds) and it incorporated all lessons learned up to that point. The new design included barrel handle, new bipod, new buttstock, updated housing, and other improved features. Over 250 rounds had been fired from the weapon action in a test fixture by that point.

As of May 2010, a formal assessment was planned 2011, with the hardware (8 LMGs configured for the telescoped ammunition) to be available by May 2011. By that time representatives of all US Armed Forces had tested the LMG configured for the telescoped ammunition, as had representatives of the Canadian and United Kingdom armed services. It was suggested at that time that a potential first unit equipped could come as early as 2016.

By FY12 the program, which had been renamed Lightweight Small Arms Systems (LSAS), involved reorienting the effort to demonstrating caseless and case telescoped ammunition technologies for specific weapon systems and missions with goals to reduce the weapon and ammo weight, and to reduce training and maintenance costs.

The proposed FY14 budget the JSSAP as a whole experienced significant funding realignment to focus on efforts deemed to be high priority. The proposed FY14 budget included no funding for the LSAS program. It did, however, include funding for research, development, test, and evaluation work on a universal projectile concept for small arms that could potentially leverage work from the LSAS program.

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Page last modified: 21-05-2013 10:43:56 ZULU