Preliminary Design and Analysis of an Environmentally Friendly 5.56 mm Bullet to Replace the M855

Abstract : The University of Texas at Austin's Institute for Advanced Technology (IAT) performed a configuration design and aeroballistic performance characterization study of a 5.56 mm bullet suitable for replacement of the existing M855 ball ammunition, which has a full metal jacket with lead alloy core and a steel penetrator. The scope of the study effort was to evolve a suitable, environmentally friendly replacement round that is compatible with the M249, M16 family, and M4 series weapons. Principal features of the conceptual design are an improved ballistic coefficient and replacement of lead antimony in the bullet core with a LiquidMetal Technologies (LQMT) penetrator core. Aerodynamic characterization via computational fluid dynamics modeling has been accomplished to facilitate flight dynamic simulation. The LQMT high-density core easily penetrates steel targets, and the truncated projectile boattail provides less resistance to tumbling in a soft target. The unitary LQMT penetrator profile is scalable to any rifle or machine gun bullet with only minor changes in mass distribution and, hence, flight characteristics. The IAT was assisted in this effort by New Jersey-based consultants Frank Brody and Roy Kline, who provided invaluable consulting expertise in small-caliber projectile design.