[7] Development began with the two types of weight-reducing ammunition, and a light machine gun to serve as a testbed and technology demonstrator.

It has several features conducive to its use as a light machine gun, such as a quick-change barrel, a vented handguard, a belt feeding mechanism, provisions for the use of an ammunition pouch, and a rate of fire of approximately 600 RPM.

Other features include its light weight, an ammunition counter, and a highly stiff and heat resistant barrel achieved with the use of fluting and specialized alloys.

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 September 2011, 19 soldiers participated in a two-week assessment of the LSAT light machine gun at Fort Benning, Georgia to demonstrate its capabilities against the M249 SAW.

Another test had the soldiers sprint 200 yards wearing body armor and a basic load of ammunition, then rapidly engage close-range targets.

A third week involved soldiers of the 75th Ranger Regiment performing a squad maneuver live-fire exercise in an urban setting.

[12] The eight prototype weapons fired a combined 25,000 rounds, moving its cased telescoped ammunition to technology readiness level 7.

[8] The LSAT light machine gun was assessed in the Army's Dismounted Non-Networked Experiment (DNNE) in August 2013 at Fort Benning.

[13] It was among several items showcased at an event at Fort Benning through 24 September 2013 featuring the Army's latest individual and squad kit developments.

[17] On 14 May 2014, Textron Systems was awarded a two-year $5.7 million contract for work that included development of 7.62 NATO cased-telescoped ammunition and an operating mechanism to incorporate into the LSAT machine gun to create a lightweight 7.62 mm version.

[18][19] Textron unveiled their 7.62 mm cased-telescoped machine gun design at the 2015 Special Operations Forces Industry Conference.