- Program Areas
- Energy and Water
- Environmental Restoration
- Munitions Response
- Resource Conservation and Resiliency
- Weapons Systems and Platforms
Elimination of Perchlorate Oxidizers from Incendiary Projectile Compositions
The objective of this project is to incorporate an improved perchlorate-free pyrotechnic incendiary composition into the following Army and Navy .50 caliber ammunition items: M8 Armor-Piercing-Incendiary (API) and MK257 Armor-Piercing-Incendiary Dim Tracer (API-DT). In a teaming effort, Army and Navy will conduct the formulation scale-up and optimization, while ATK Lake City Army Ammunition Plant (LCAAP) will perform the initial demonstration. Final performance qualification of the M8 and MK257 will be conducted at LCAAP and Naval Surface Warfare Center (NSWC) Crane, respectively. The new composition will contain optimized fuels and perchlorate-free inorganic oxidizers and produce equal or superior incendiary performance. The perchlorate-free formulation will undergo joint Navy and Army formulation qualification.
The vast majority of current in-service incendiary projectiles (.50 caliber M8 API, M20 API-Tracer, MK257-DT, 20-mm PGU 28/B, 20-mm M940 and 40-mm M918) contain potassium perchlorate as an oxidizer. However, under SERDP project WP-1424, it was shown that the perchlorate ingredient can successfully be eliminated without adversely affecting the incendiary projectile performance in terms of flash size and burn times. This was accomplished using non-chlorine oxidizers and binders/processing aids. Extensive studies were also performed to ensure that there were minimal environmental impacts. The computer modeling program NASA CEA2 (Chemical Equilibrium with Applications) was used to determine the combustion products for a range of pyrotechnic compositions. In addition to static tests of lab pellets, gun fire tests were also performed. In the case of the M8 API and MK257-DT, the most successful perchlorate-free candidate composition discovered contains optimized weight percentages and particle size distributions of magnesium/aluminum alloy, sodium nitrate, and calcium resinate. Other perchlorate-free formulations (Mg/Al alloy and aluminum powder with strontium nitrate) have also been proven-out in different pyrotechnic applications and found viable.
Perchlorate-free pyrotechnic compositions will eliminate the adverse impact of perchlorates on the environment during manufacturing, testing, deployment, and demilitarization. The elimination of perchlorate from these compositions will also lead to a reduction in future cleanup or potential litigation costs at military facilities contaminated by perchlorate during the life cycle of the items. Having environmentally acceptable M8 API/MK257 API-DT available in the service inventories will also avoid disruptions in training schedules should restrictive limits on perchlorates be set. (Anticipated Project Completion - 2014)