The milestone was achieved the Lake City Army Ammunition Plant in Independence, Mo.
"I am very proud of what ATK has delivered for the U.S. Army while being entrusted with our stewardship responsibility to safely and efficiently operate the Lake City Army Ammunition Plant," said ATK Defense President Mike Kahn. "We value our commitment to deliver a lean, scalable and sustainable capability that will serve the needs of our nation for years to come."
STK Defense took control of operations at the Lake City plant in 2000 partnership with the U.S. Army. It expanded and modernized facilities, resulting in a rise in production -- from 374 million rounds a year than 1.6 billion rounds annually.
In that production figure is the U.S. Army's M855A1 Enhanced Performance Round, an enhanced version of the M855 5.56mm cartridge.
ATK said it has delivered more than 350 million M855A1 rounds since transitioning to production in 2010.
ATK said it recently received orders for $131 million from the Army for 5.56mm, 7.62mm and .50-caliber ammunition. All will be produced at the Missouri facility.