The pyrotechnics division of the Armament Research, Development and Engineering Center, at Picatinny Arsenal, N.J., is developing a more environmentally friendly formula for armor-piercing incendiary projectiles. (Percy Jones / Army)
Researchers at Picatinny Arsenal, N.J., are working to remove two harmful chemicals from .50-caliber armor-piercing incendiary projectiles, which can be fired from the M2, M3 and M85 machine guns.
Army Research, Development and Engineering Command is developing a replacement incendiary mix for these rounds to eliminate the chemicals barium nitrate and potassium perchlorate, which can leech into ground water and cause health problems.
“The biggest environmental impact and the biggest compromise to the Army mission is when the toxins permeate the ground water on U.S. territory,” Jared D. Moretti, a chemist with ARDEC’s pyrotechnics division, told Army Times.
“These chemicals, particularly the potassium perchlorate, are very persistent in ground water plumes, which means if they can penetrate to our water supply, they can dissolve and remain there for some time,” Moretti said. “Inevitably, costs have to be incurred to remediate them.”
Moretti said the health and environmental impact of munitions have long been a concern of the Army’s, but the effort follows studies that indicate that some barium compounds and perchlorates can harm people and the environment.
Both barium nitrate and potassium perchlorate are useful for “after-armor effects,” meaning the incandescent flash when penetrating a hard target and for igniting fuel in, say, a vehicle’s gas tank.
Barium nitrate can cause serious digestive, cardiac, respiratory and muscular problems. Potassium perchlorate can interfere with thyroid function, which regulates the metabolism, and it can be harmful to pregnant women and their unborn children.
Researchers plan to remove the two substances from the IM-28 baseline mixture and replace them with the chemical sodium metaperiodate.
Moretti said he was familiar with sodium metaperiodate from his work as a graduate student at the University of Pittsburgh. The substance is used routinely in organic chemistry, by the pharmaceutical industry, in cleaning products and as a metal etching solution.
Working with the Naval Surface Warfare Center at Crane and Alliant TechSystems, known as ATK, the Pyrotechnic Division tested a range of formulations that varied in composition.
Army Public Health Command is conducting an environmental health assessment of sodium metaperiodate.
“My intuition is there won’t be any real issues with this, and this is not a regulated compound,” Moretti said.
Initial tests showed sodium metaperiodate was amenable to manufacturing environment at Lake City Army Ammunition Plant, Mo.
Performance tests are ongoing. Moretti predicted the round would not be in soldiers’ hands in three years.
In 2008, Army researchers at Picatinny devised perchlorate-free training weapons over similar environmental and health concerns. In non-lethal munitions, the substance is used to create a loud bang and bright flash.