The Springfiels Armory Museum, Springfield Mass. , part of the National Park System has a great history of the M1 rifle. If I could post pictures here I'd show you a nice closeup photo of the receiver of "U.S.Rifle, Cal..30M1, Springfield Armory, 81. Serial # 81 was ythe first rifle to go to the US military for testing. Also serial #100,000 1,000,000 etc. If any of you are ever in Massachusetts this museum is a must see, and it's free. Also if in the area, the Wadsworth Museum in Hartford CT has a display right now of the Colt firearms.
John M. A Connecticut Yankee