The Joint Service Small Arms Program first began investigating the benefits of caseless ammunition in the 1980s, which culminated in the demonstration of a caseless ammunition assault rifle system, the G11, during the Advanced Combat Rifle program.
In 2004, the interest in caseless ammunition was renewed because of its ability to reduce load and overall volume, and a caseless ammunition development was included as part of the Lightweight Small Arms Technologies (LSAT) program. Under LSAT, and with funding provided by the Office of Naval Research, the propellant formulation developed for the ACR program was successfully replicated, and then scaled up to the cylindrical 5.56mm configuration needed for LSAT.
A small pilot plant was then built to manufacture the ammunition. A Technology Readiness Level (TRL) 5 was demonstrated in June 2008, and 1,000 rounds were delivered for testing in the caseless weapon system, which had been developed in concert with the ammunition. Once the feasibility of the caseless technology was shown, the next step was to address the manufacturability and cost implications of this unique item. With the key parameters fixed for impetus ballistics), flame temperature, and mechanical strength, an effort was undertaken to optimize the propellant formulation and manufacturing process for large-scale production, similar to current small caliber production.
Current efforts are focused on optimizing the formulation for ballistic performance, with iterations of propellant blends molded into cartridge configuration and tested in a Mann barrel. The TRL 5 assessment for this effort is scheduled for December 2010. If successful, caseless ammunition could revolutionize infantry operations and have a significant impact on vehicle mounted system and logistics. Final decisions on program transition are still being made based on the outcome of the efforts described above.