Founded in 1919, O.F. Mossberg & Sons, Inc. is the oldest family-owned firearms manufacturer in America, and is the largest p ... ump-action shotgun manufacturer in the world. Leading the way with over 100 design and utility patents to its credit, and standing as the first ISO 9001 Certified long-gun manufacturer, Mossberg is considered to be one of the most innovative firearms manufacturers in U.S. History. Mossberg has facilities located in North Haven, CT and Eagle Pass, TX. read more