The M1A is a civilian version of the M14 rifle designed and manufactured by Springfield Armory, Inc. in 1974. The term "M1A" is a proprietary title for Springfield Armory's M14 pattern rifle. Early M1A rifles were built with surplus G.I. parts until Springfield Armory, Inc. began manufacturing their own.
Springfield Armory M1A Manual 2013-09-10
User manual for the M1A Rifle