1894cfan: there is only one way to positively identify when your rifle was made and that is to pack it up, along with all the ammo ya got for it, and send it on over to me for a very lengthy evaluation and analysis. Ya don't hafta listen to Mr. AtlLaw as he is maneuverin' his-self to get you to the same point, to send it to him that is. Ya gotta unnerstand that he is a tricky devil. He would prolly first want ya to send him just the barrel for a looksee but then he would talk ya into sendin' him the whole dang thing, so ya gotta be careful with him ya know, especially since he said he would be 'interested'.........
A issue rifle should have a Ordinance mark/stamp on the barrel, usually on the underside of the barrel - it would be a flaming bomb with a number and that should tell you when the rifle/barrel were made or commissioned. Or, as AtlLaw suggested, you could probably google it yourself although I am certain there are many here who unlike me and AtlLaw would not ask you for the rifle first, maybe.........