The Lightweight Small Arms Technologies (LSAT) program is funded by the U.S.
Joint Service Small Arms Program
The Joint Service Small Arms Program, abbreviated JSSAP, was created to coordinate weapon standardization between the various United States armed service branches.
First Project - XM9 Procurement
In 1962, the Air Force adopted the Smith ...
, with the goal of significantly reducing the weight of
small arms and their
ammunition.
Following a series of military programs to investigate advances in small arms (
SPIW
The Special Purpose Individual Weapon (SPIW) was a long-running United States Army program to develop, in part, a workable flechette-firing "rifle", though other concepts were also involved. The concepts continued to be tested under the Future Ri ...
, Future Rifle,
ACR,
OICW
The Objective Individual Combat Weapon or OICW was the next-generation service rifle competition that was under development as part of the United States Army OICW program; the program was eventually discontinued without bringing the weapon out of ...
), the LSAT program is the
US military
The United States Armed Forces are the Military, military forces of the United States. The armed forces consists of six Military branch, service branches: the United States Army, Army, United States Marine Corps, Marine Corps, United States N ...
's latest project to replace existing US small arms. Tactical concepts and the research from the previous small arms programs indicates that lightening small arms is the first significant step towards increasing soldiers' lethality and survivability.
Initiated in 2004 (then called the Lightweight Machine Gun and Ammunition program), development is now led by
Textron
Textron Inc. is an American industrial conglomerate based in Providence, Rhode Island. Textron's subsidiaries include Arctic Cat, Bell Textron, Textron Aviation (which itself includes the Beechcraft, and Cessna brands), and Lycoming Engin ...
. Development began with two types of weight reducing ammunition, and a
light machine gun
A light machine gun (LMG) is a light-weight machine gun designed to be operated by a single infantryman, with or without an assistant, as an infantry support weapon. LMGs firing cartridges of the same caliber as the other riflemen of the sa ...
to serve as a
testbed
A testbed (also spelled test bed) is a platform for conducting rigorous, transparent, and replicable testing of scientific theories, computational tools, and new technologies.
The term is used across many disciplines to describe experimental rese ...
and technology demonstrator.
Minimization of program risk is shown by the development of the lower performing but less risky
polymer-cased ammunition
Polymer-cased ammunition (PCA) is firearm ammunition ( cartridge) with casings made from synthetic polymer instead of the typical metallic casing. PCA is considered a new alternative that potentially reduces production cost and weight for long ...
alongside
caseless ammunition (which falls higher in both criteria), by the use of extensive computer simulations before prototyping, and by the use of existing and proven technologies, such as the High Ignition Temperature Propellant (HITP) developed for the
Heckler & Koch G11
The Heckler & Koch G11 is a non-production prototype assault rifle developed from the late 1960s–1980s by ''Gesellschaft für Hülsenlose Gewehrsysteme'' (GSHG) (German for "Association for Caseless Rifle Systems"), a conglomeration of compan ...
.
In 2008, the program had achieved working prototypes for the polymer-cased ammunition and the
LMG, which were tested by the Army in 2012. The less orthodox
caseless
Caseless ammunition (CL), or rather caseless cartridge, is a configuration of weapon-cartridge that eliminates the cartridge case that typically holds the primer, propellant and projectile together as a unit. Instead, the propellant and primer ...
ammunition, and a rifle firing both types of ammunition, have also been developed. The designers aim to provide further projectile improvements, including greener bullets and a more lethal
caliber,
as well as the use of electronics, such as
rounds counters, and
lasers
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The fir ...
for sighting, target acquisition, and steering.
After further research and development into both ammunition types and the weapons that fire them, one of the two shall be chosen for production.
In August 2013,
AAI Corporation
AAI Corporation is an aerospace and defense development and manufacturing firm, located in Hunt Valley, Maryland, US. Formerly a wholly owned subsidiary of United Industrial Corporation, AAI was acquired by Textron in 2007. It currently operate ...
(now Textron) was awarded a contract to continue development of both cased telescoped and caseless ammunition.
Background
The Lightweight Small Arms Technologies program is the culmination of much research and information obtained by the US Army. It succeeds several other programs to develop new
small arms technologies, each program of which produced results that were infeasible or insignificant. The first three (the
Special Purpose Individual Weapon
The Special Purpose Individual Weapon (SPIW) was a long-running United States Army program to develop, in part, a workable flechette-firing "rifle", though other concepts were also involved. The concepts continued to be tested under the Future Ri ...
, the
Future Rifle Program, and the
Advanced Combat Rifle
The Advanced Combat Rifle (ACR) was a United States Army program, started in 1986, to find a replacement for the M16 assault rifle. Under the stress of battle the average soldier with an M16 may shoot a target at 45 meters, but hit probability is ...
program) demonstrated the ballistic problems of
flechette ammunition, and the
ACR program also showed the inability of kinetic-energy firearms to significantly compensate for human inaccuracy (the small accuracy increase of all of the concepts tested was out-weighed by the trade-offs required). The subsequent identification of programmable air-bursting munitions as the only way to significantly increase accuracy was followed by the fourth, and most recent, cancelled program—the
OICW
The Objective Individual Combat Weapon or OICW was the next-generation service rifle competition that was under development as part of the United States Army OICW program; the program was eventually discontinued without bringing the weapon out of ...
program. The ability to detonate an explosive in the air at range provided a huge increase in accuracy, but the resultant
XM29
The XM29 OICW (''Objective Individual Combat Weapon'') was a series of prototypes of a new type of assault rifle that fired 20 mm HE airbursting projectiles. The prototypes were developed as part of the Objective Individual Combat Weapon p ...
proved too heavy to use. The separation of the XM29 into the
XM25 and the
XM8
The Heckler & Koch XM8 is a lightweight assault rifle system developed from the late 1990s to early 2000s. The rifle was designed by German small arms manufacturer Heckler & Koch (H&K), and shares design and engineering with their G36 rifle.
...
provided no long-term solution to the weight problem, and the program was suspended indefinitely. Developments in lighter weapons (such as LSAT) could see a return to the concept, although the military has not recently expressed a desire for a return. The indefinite suspension of the program sounded the death of short-term advances in infantry weapon lethality, and indicated the shift to other projects.
After the failure to significantly improve firearms of the near future, the
U.S. military is using the development of other infantry equipment to improve the effectiveness of the soldier. Most notable is the development of
electronics
The field of electronics is a branch of physics and electrical engineering that deals with the emission, behaviour and effects of electrons using electronic devices. Electronics uses active devices to control electron flow by amplification ...
and information technology to advance soldiers' awareness and communications (as with the
Land Warrior
Land Warrior was a United States Army program, launched in 1994, cancelled in 2007 U.S. Army Budget Request Documents FY2008 (page 4) but restarted in 2008,http://www.army-technology.com/projects/land_warrior/ Land Warrior at Army-Technology.com ...
program). However, this new equipment increases the weight burden on the soldier, who then has to strike a compromise between the extra equipment and mobility. Reducing the weight of infantry equipment allows for more mobile, better equipped troops. Since a soldier's weapon and ammunition are a large portion of his total burden (and available technologies exist to sharply lighten them), reducing the weight of the two is crucial to increasing the amount of advanced technology a soldier can carry.
Computer technologies integrated into the weapon and its sights make a light weapon crucial, otherwise the soldier will have difficulty carrying the weapon and its heavy sights. Other indirect improvements in soldier effectiveness include new strategies and the development of air transport. This is aimed towards creating fast, well-equipped soldiers able to be quickly deployed to counter threats.
The logistics and mobility problems of heavy equipment hinder this possibility.
The LSAT program allows a vast reduction in soldiers' carrying loads, thereby allowing new and more equipment, reducing logistical strain, and increasing mobility. The combined benefits to soldier effectiveness are big enough to warrant the investment in the new lightweight technologies.
Technologies
The existence of weight-reducing technologies made the LSAT program feasible, and many of these technologies can be seen in the program's products. The lightest existing ammunition to fire standard bullets comprised
caseless
Caseless ammunition (CL), or rather caseless cartridge, is a configuration of weapon-cartridge that eliminates the cartridge case that typically holds the primer, propellant and projectile together as a unit. Instead, the propellant and primer ...
varieties. The
Heckler & Koch
Heckler & Koch GmbH (HK; ) is a German defense manufacturing company that manufactures handguns, rifles, submachine guns, and grenade launchers. The company is located in Oberndorf am Neckar in the German state of Baden-Württemberg, and also ...
G11 was the only weapon to achieve a service capable assault rifle firing caseless ammunition. Its unique ammunition, designed by
Dynamit Nobel
Dynamit Nobel AG is a German chemical and weapons company whose headquarters is in Troisdorf, Germany. It was founded in 1865 by Alfred Nobel.
Creation
After the death of his younger brother Emil in an 1864 nitroglycerin explosion at the fam ...
, introduced several important innovations, such as improved internal ballistics through the use of a primer, and the prevention of
cooking off
Cooking off (or thermally induced firing) is unfired weapon ammunition exploding prematurely due to heat in the surrounding environment. The term is used both for detonation of ammunition not loaded into a weapon, and unintended firing of a loa ...
(the lack of a case makes it easier for a hot chamber to ignite the exposed propellant) through the use of the less sensitive
hexogen
RDX (abbreviation of "Research Department eXplosive") or hexogen, among other names, is an organic compound with the formula (O2N2CH2)3. It is a white solid without smell or taste, widely used as an explosive. Chemically, it is classified as a ...
/
octogen as the explosive component. The
Advanced Combat Rifle
The Advanced Combat Rifle (ACR) was a United States Army program, started in 1986, to find a replacement for the M16 assault rifle. Under the stress of battle the average soldier with an M16 may shoot a target at 45 meters, but hit probability is ...
experimental program gave the US Army access to the ammunition and entrenched the ammunition as a viable option. With the high efficiency and lethality of the ammunition, the vast expenditure such a concept had needed for development, and the reduced risk of using an already proven ammunition design, the LSAT program chose a licensed version of Dynamit Nobel's caseless ammunition as a route towards its goal of weight reduction. The LSAT program also uses the same concept of a rotating chamber as the G11 (albeit, the LSAT
LMG chamber swings around a longitudinal pivot.
whereas the G11 chamber rotated around a horizontal axis at its very centre).
Polymer casing for ammunition had already been developed and produced, and it provided the second route for achieving weight reduction. While a polymer case could never be quite as light as no case, the risks involved in the use of polymer ammunition were less, due to its similarity to present ammunition and the reduced heat load on both the weapon and the ammunition's propellant.
Further budding technologies, such as alternative barrel materials (such as
ceramic
A ceramic is any of the various hard, brittle, heat-resistant and corrosion-resistant materials made by shaping and then firing an inorganic, nonmetallic material, such as clay, at a high temperature. Common examples are earthenware, porcelain ...
s), and the increased efficiency and size reduction of
telescoped ammunition
Telescoped ammunition is an ammunition design in which the projectile is partially or completely enveloped by the propellant. Examples include ammunition for both hand weapons and artillery. Caseless ammunition is often telescoped.
Telescoped ...
(used by the G11 and other developmental weapons), also formed the basis for the LSAT program.
Program
In 2004, the
Joint Service Small Arms Program
The Joint Service Small Arms Program, abbreviated JSSAP, was created to coordinate weapon standardization between the various United States armed service branches.
First Project - XM9 Procurement
In 1962, the Air Force adopted the Smith ...
created the Lightweight Machine Gun and Ammunition program to compare conceptual, lightweight machine guns and ammunition designs by two teams of companies. The team of eight, led by
AAI Corporation
AAI Corporation is an aerospace and defense development and manufacturing firm, located in Hunt Valley, Maryland, US. Formerly a wholly owned subsidiary of United Industrial Corporation, AAI was acquired by Textron in 2007. It currently operate ...
had their design chosen over the design of the General Dynamics-led team. In 2005, the project was replaced with the Lightweight Small Arms Technologies program to place the emphasis on developing technologies for a wide range of small arms. The earlier Lightweight Family of Weapons and Ammunition concept is visible in the new program. The cohesive team of companies is combined with government support to ensure success.
In accordance with the program's name, the focus is on creating lightweight technologies for all small arms, and the
Light Machine Gun
A light machine gun (LMG) is a light-weight machine gun designed to be operated by a single infantryman, with or without an assistant, as an infantry support weapon. LMGs firing cartridges of the same caliber as the other riflemen of the sa ...
it has started with is an entry point for a family of lightweight small arms and ammunition. Beginning with an LMG is unusual for an effort to develop a new family of weapons, although the increased engineering difficulty of a machine gun over a rifle is balanced against decreased attention and antagonistic scrutiny. The program minimized development risk: it used G11 technology that had been on the verge of deployment; and the parallel development of the composite-cased and caseless ammunition meant that, if the caseless ammunition effort succeeded, much of the development work gained with the composite cased weapon could be applied to it, and, if it failed, the composite-cased version was likely to succeed on its own.
This parallel development involves using what is essentially the same weapon for both types of ammunition, with the same action (having only marginal differences, such as added chamber sealing technologies required for the caseless firing version) and the same weight-lowering technologies.
The program uses extensive computer simulation and modelling, particularly of the weapon action. This reduces both time and expenditure for prototyping and testing. The program also uses a '
spiral development' approach,
whereby the weapon and ammunition is rolled out in stages or 'spirals', each stage producing a new version that is an improvement on those from previous spirals.
The LSAT program uses a 'clean slate' design and had no requirements imposed on abiding by contemporary ammunition and weapon standards. Despite this, the program is using the
M855 5.56×45mm round to provide comparison with existing weapons. The program has listed scalability of the ammunition calibre as a requirement, and its pursuit of a very light company machine gun would require a larger round. Therefore, the program seems set towards a more accurate, harder-hitting round (such as the
6.5 mm Grendel or
6.8mm Remington SPC
The 6.8mm Remington Special Purpose Cartridge (6.8 SPC, 6.8 SPC II or 6.8×43mm) is a rimless bottlenecked intermediate rifle cartridge that was developed by Remington Arms in collaboration with members of the U.S. Army Marksmanship Unit and U ...
).
The program has set itself weight reduction goals over the existing
M249
The M249 light machine gun (LMG), also known as the M249 Squad Automatic Weapon (SAW), which continues to be the manufacturer's designation, and formally written as Light Machine Gun, 5.56 mm, M249, is the American adaptation of the Belgian F ...
and
its ammunition of 35% for the weapon and 40% for the ammunition. Further goals to improve battlefield effectiveness have also been set: improved lethality; improved controllability (through recoil reduction, etc.); improved ergonomics; improved reliability and maintainability; integration of electronics; and equivalent cost and producibility to the existing weapon and ammunition.
Achievements
By 2008, the program had made tremendous progress, with all of its goals either fully achieved or with strong potential for achievement.
Light machine gun
The
LMGs built made a 47% and 43% reduction of weight for the caseless weapon and cased telescoped weapons, respectively. The more complex chamber-sealing mechanism of the caseless weapon somewhat increases its weight compared to the composite-cased weapon. Secondary goals have also been met: the LMG has the potential to improve battlefield effectiveness (due to its simpler and more consistent weapon action, its light weight and low recoil, and its stiffer barrel); its use of recoil compensation (with a long-stroke gas-system, for example) has produced positive feedback regarding controllability; the simpler mechanism of the LMG is both more reliable and easier to maintain; a rounds counter has been integrated to improve maintainability, and the weapon is capable of accepting other electronic devices; improved materials used in the chamber and barrel have reduced heat load on the weapon; and the weapon cost is equivalent to the existing
M249
The M249 light machine gun (LMG), also known as the M249 Squad Automatic Weapon (SAW), which continues to be the manufacturer's designation, and formally written as Light Machine Gun, 5.56 mm, M249, is the American adaptation of the Belgian F ...
.
The LMG design is a traditionally (non-
bullpup) laid-out machine-gun. It has many of the capabilities of other
light machine guns
A light machine gun (LMG) is a light-weight machine gun designed to be operated by a single infantryman, with or without an assistant, as an infantry support weapon. LMGs firing cartridges of the same caliber as the other riflemen of the sam ...
, such as a quick-change barrel, a vented fore-grip, belt-fed ammunition, an ammunition pouch, and a roughly 600
rpm rate of fire. New features include the unique weight of 9.2 pounds for CT and 9.9 pounds for CL,
a rounds counter, and a highly stiff and heat resistant barrel achieved with fluting and special materials.
Possibly the most radical part is its firing action: the weapon uses a swinging chamber. The chamber swings around a longitudinal pivot; it swings from horizontally parallel with the pivot (the firing position), to vertically parallel (the feed position), and back again.
A long-stroke gas-piston is used to operate this action. A round is fed into the chamber at the feed position using a rammer, and the new round also serves to push a spent or dud round out of the far end of the chamber. Such rounds are pushed forward, parallel to the barrel, and they slide into a separate mechanism that ejects them out of one side of the gun. The advantages of this whole action include its simplicity, its isolation of the chamber from barrel heat, and its positive control of round movement from extraction to ejection. In the caseless firing version of the weapon, another mechanism is introduced to seal the chamber during firing (which is why the caseless weapon is heavier).
Assault rifle
Design of an LSAT battle rifle began in 2008.
Halfway into 2008, the designs are nearing completion. The rifle designs are made to use the same cartridge as developed for the LMG, and this means separate rifles are being designed for the cased and caseless cartridges. Design began with seventeen concepts; after the concepts were investigated and trade-offs were analysed, only two remained for the cased round, and two for the caseless round.
The concepts involve two magazine approaches, both of which are focussed on high capacity: one uses the standard approach of placing inside the magazine springs that feed rounds into the weapon; the other uses a 'weapon powered' approach, presumably to reduce the extra weight and space that springs create in magazines.
If any of the rifle designs use the same swinging chamber mechanism as the LMG, they should be well suited to a
bullpup layout, since the forward ejection of the push-through feed-and-ejection mechanism could easily be extended to achieve full ambidexterity, which is a problematic absence in most bullpups. Even in other configurations, the push-through mechanism lends itself very well to
ambidexterity
Ambidexterity is the ability to use both the right and left hand equally well. When referring to objects, the term indicates that the object is equally suitable for right-handed and left-handed people. When referring to humans, it indicates that ...
: the
G11 demonstrates this. The rifle designs are undergoing the same simulated, structural, and kinematic analyses as the LMG.
On May 14, 2014,
Textron Systems
Textron Inc. is an American industrial conglomerate based in Providence, Rhode Island. Textron's subsidiaries include Arctic Cat, Bell Textron, Textron Aviation (which itself includes the Beechcraft, and Cessna brands), and Lycoming Engines. I ...
was awarded a two-year $5.7 million contract for work that included development of a carbine firing cased-telescoped ammunition.
Ammunition
The cylindrical shape of the ammunition is crucial to the weapon's straight-through feed-and-ejection system, and it is the similar shape of the cased-telescoped ammunition to the caseless-telescoped ammunition that allows the parallel development of the two weapon systems. Telescoped ammunition's most notable benefits include the greater propulsive effectiveness of a telescoped round over standard ammunition, and the shorter feed and action times allowed by the shorter length of a telescoped round (both the cased and caseless designs are roughly 30% shorter). If the weapon and ammunition prove superior to existing weapons, a new caliber may be chosen. An intermediate round with characteristics similar to the
6.5 mm Creedmoor is being considered along with the possibility of using a common round in more roles including
GPMG
A general-purpose machine gun (GPMG) is an air-cooled, usually ammunition belt, belt-fed machine gun that can be adapted flexibly to various tactical roles for light machine gun, light and medium machine guns. A GPMG typically features a quick-c ...
and
marksman
A marksman is a person who is skilled in precision shooting using projectile weapons (in modern days most commonly an accurized scoped long gun such as designated marksman rifle or a sniper rifle) to shoot at high-value targets at longer-than- ...
weapons.
While M855 and M855A1 projectiles are being used for comparison and demonstration purposes, consideration is being given to using the creation of lightweight ammo cases as a chance to develop an intermediate caliber cartridge which might replace both the 5.56×45mm and the 7.62×51mm. Suggested characteristics of the cartridge are a 6.5 mm bullet weighing 120 gr that can match the effectiveness of the 7.62×51mm at 1,000 m.
Cased
The cased ammunition is more advanced in development, partially due to the fewer technical difficulties and the fewer differences with standard ammunition. It has already reached the required
technology readiness level of 5. As of 2008, the cased ammunition has been tested for a wide range of
operating temperatures, and it has had over 9000 rounds fired (approximately 6500 rounds of Spiral 1 ammunition, and over 2000 of Spiral 2). The second spiral version of the cased ammunition produced a 33% weight reduction (falling just short of the program goal), while the ongoing development of the third spiral of cased ammunition has achieved a roughly 40% reduction. The third spiral is also 30% smaller than standard ammunition. The improvement by the third spiral of cased ammunition over the second spiral was achieved partially by compacting and consolidating the propellant (thereby allowing a smaller cartridge case and round). Having reached a sufficient
technology readiness level, the Spiral 2 ammunition is being prepared for a contracted 2000 round delivery. The cased ammunition has shown itself as a virtually risk free option, with present and potential ability grounded in success. In addition, development of the cased ammunition firing weapon has significantly improved understanding of the weapon action and requirements.
Cased telescoped ammunition for the
LSAT light machine gun reached
technology readiness level 7 after 25,000 rounds were fired in trials in 2011.
Caseless
Having replicated
Dynamit Nobel
Dynamit Nobel AG is a German chemical and weapons company whose headquarters is in Troisdorf, Germany. It was founded in 1865 by Alfred Nobel.
Creation
After the death of his younger brother Emil in an 1864 nitroglycerin explosion at the fam ...
's
ACR ammunition, the HITP (High Ignition Temperature Propellant—it is
hexogen
RDX (abbreviation of "Research Department eXplosive") or hexogen, among other names, is an organic compound with the formula (O2N2CH2)3. It is a white solid without smell or taste, widely used as an explosive. Chemically, it is classified as a ...
/
octogen based to decrease heat sensitivity) based ammunition was modified to a
5.56 mm round. Tests proved the ammunition's usability, and development of the weapon was advanced using knowledge gained from the cased ammunition version. The
Alliant Techsystems ammunition production team has reduced the production time and costs by reducing from fourteen to two the number of steps used to complete processing.
The second spiral of caseless ammunition was rolled out in 2008, with the necessary facilities to produce the ammunition in bulk completed.
It has vastly reduced the weight and volume of standard ammunition (by 51% and 40%, respectively), and it has reached the verge of achieving Technology Readiness Level 5. The development of the third spiral was also initiated, with the goal of replacing the propellant binder with a binder more environmentally and cost friendly.
It also aims to reduce the heat ablation on the inside of the weapon by modifying the burn rate of the propellant, and by giving the round an exterior coating to absorb or prevent transferred heat.
Benefits the system has gained from using the caseless ammunition go beyond the unparalleled weight and volume reduction to, for example, the lack of ejected shells (which both improves the weapon's protection from dirt and removes any need to 'police' cases after firing). The ammo was still in development as of 2012.
See also
*
Future Combat Systems
Future Combat Systems (FCS) was the United States Army's principal modernization program from 2003 to early 2009. Formally launched in 2003, FCS was envisioned to create new brigades equipped with new manned and unmanned vehicles linked by an unpr ...
*
Future Force Warrior
Future Force Warrior was a United States military advanced technology demonstration project that was part of the Future Combat Systems project. The FFW project sought to create a lightweight, fully integrated infantryman combat system. It was one ...
References
External links
Army.mil article*
ttps://www.scribd.com/doc/26503475/Lightweight-Small-Arms-Technologies Scribd.com articleDefense UpdateDocstoc.com article
{{Textron
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