The $8.8 million option for the load, assemble and pack of the MACs modifies an existing contract awarded in December 2008.
The MACS provides propelling charges with combustible cartridge cases for 155mm artillery. The charges are compatible with new and existing howitzer systems and offer enhanced precision with a reduction in weight and volume.
Production work will be performed at General Dynamics' facility in Camden, Ark. Program support will occur at the company's Williston, Vt., facility.
General Dynamics said work on the option will be completed by September 2013.
"MACS offers maximum flexibility in tactical logistics to U.S. warfighters," said Steve Elgin, vice president and general manager of armament systems for General Dynamics Armament and Technical Products.
"The build-a-charge system eliminates the need to dispose of unused cartridges and the charge system fires cleanly, without leaving residue in the cannon breech."