Granite State Manufacturing

Founded in 1937, Granite State Manufacturing is a defense subsystem manufacturer based in Manchester, United States working in naval systems, mro & logistics.

Granite State Manufacturing (GSM) is a family-owned precision manufacturer based in New Hampshire, with facilities in Manchester and Nashua. The company produces CNC-machined and welded components that are used in U.S. Navy submarine systems, including Virginia-class and Columbia-class submarines. Its work includes five-axis machining, large-format welding, fabrication and assembly, with parts up to 30-foot structural assemblies. GSM operates to AS9100D and ISO 9001:2015 quality management systems and is ITAR registered. The company supplies the submarine industrial base and has been in operation since 1937. It also runs workforce development initiatives, including free welding and machining training programs, aimed at building the skilled labour pool needed for submarine manufacturing.