Description:
TECHNOLOGY AREA(S): Weapons
OBJECTIVE: Develop test techniques, methodologies and fixture(s) for design, development and demonstration of caseless small caliber ammunition technology.
DESCRIPTION: The DoD is interested in developing propellants suitable for small caliber caseless ammunition to reduce ammunition weight, reduce sensitivity, and increase lethality. Developments include new propellant formulations, propellant ignition methods, and ammunition cartridge design/layout. Recent research into lower sensitivity propellants, which are much more difficult to ignite compared to conventional nitrate ester propellants, has revealed the need for greater understanding of the ignition process. Caseless ammunition replaces the metallic cartridge case and granular propellant used in conventional ammunition with a solid propellant body. The caseless propellant body makes up the structure of the ammunition cartridge and contains the projectile and igniter. The entire propellant body is consumed upon firing the cartridge. The gas generated during the ignition process pressurizes the gun chamber, eventually causing the projectile to move once the shot start force is overcome. As the projectile moves, the amount of volume in the gun chamber increases. Because the propellant gas generation rate is dependent on chamber pressure, which in turn, is dependent on chamber volume, it is crucial that the propellant ignition and flamespreading process keeps up with projectile motion. Otherwise, the propellant may not completely burn and the desired ballistic performance will not be obtained. When designing new propellant formulations and ammunition concepts, it is desirable to obtain diagnostic data about the ignition and propellant combustion processes. Data such as chamber pressure and projectile motion as functions of time are desired for validation of computer models and evaluation of the ignition process. Determination of flame propagation through the propellant charge is also of interest.
PHASE I: The offeror will develop test and measurement techniques to accelerate the development of advanced small caliber caseless ammunition. Test data of interest include chamber pressure, projectile position, and propellant combustion progress. Design a test fixture that will enable the collection of these data.
PHASE II: The offeror will construct prototype test fixtures to demonstrate the measurement techniques developed in Phase I. Perform diagnostic tests using Government specified propellants.
PHASE III: Extend the test and measurement techniques developed in this SBIR to support development additional ammunition configurations and calibers.
REFERENCES:
1: Wikipedia, "Caseless Ammunition" Website modified 26 March 2017, Accessed 6 April 2017 https://en.wikipedia.org/wiki/Caseless_ammunition
2: Spiegel, Kori and Shipley, Paul, "Lightweight Small Arms Technologies" http://www.dtic.mil/dtic/tr/fulltext/u2/a481434.pdf
3: AMCP 706-150 Engineering Design Handbook Interior Ballistics of Guns
KEYWORDS: Caseless Ammunition, Interior Ballistics, Ballistic Testing, Ammunition Development, Ignition Diagnostics
