Development of Non-Toxic Cores for Small Caliber Projectiles

The use of lead projectile cores in current U.S. Army small caliber ammunition has caused increasing concern over the environmental contamination of military firing ranges and surrounding areas. A number of military firing ranges are in danger of being closed due to high levels of lead contamination. TRI/Austin proposes to demonstrate the feasibility of developing a non-toxic, lead free, cost effective, injection molded projectile core made from a high density powder metal alloy combined with a state-of-the-art polymer binder. Compatible polymer binders with excellent adhesion will be determined by using a unique method to characterize the surface charge or zeta potential of the metallic particle surface. The powder metal alloy-polymer core will have a density similar to a lead core and will perform ballistically like a lead core. Polymer binders such as polyetherimide, polypthalimide, nylon 6,6 nylon 11 and nylon 12 will be mixed with a metal alloy such as tungsten-copper for injection molding. Degradation additives will be investigated to accelerate the polymer binder's degradation once the projectile core is spent.