In 1996, brothers Mark and Chuck Larson founded Rock River Arms in an 1,800 square foot shop in Cleveland, Illinois. Mark and Chuck together brought over 40 years of varied experience in the firearms manufacturing industry into their new endeavor. Rock River Arms soon developed a reputation as one of the finest builders of hand fitted custom 1911 pistols, and their NM frames and slides set new industry standards for tight tolerances, fit and finish. The brothers soon turned their manufacturing expertise and attention to detail into producing custom .223 caliber "AR" style rifles. Their initial focus on tightening up tolerances and improving the fit, finish and reliability of their rifles was rewarded as the Rock River Arms NM A2 Rifle quickly gained popularity among high-power shooters. Today, operating out of approximately 50,000 square foot (and growing) state-of-the-art facilities in Colona, Illinois, the company is producing a full line of custom rifles, parts and accessories, all built with the same focus on providing the finest fit, finish and function at a reasonable price..