Mine was made in 1912 and issued to the Postal Service in the 1920's.
For those of you that don't know the 1917 is a Military Designation and it's actually the Colt New Service Model. Mine has the 1917 Stamping on the frame, by the lanyard loop, as they all do if they are the "real thing".
Congrats on a great gun. Mine's a great Single Action shooter, don't care for the D.A. much in this gun. It's smooth, but very heavy.
Biker