I was given a new Colt model 1911 pistol for a graduation present a long time ago. I thing it was a fairly old pistol when it was given to me. I would like to try and find out when it was manufactured. On the left side of the slide is marked COLT SUPER .38 AUTOMATIC. On the right side of the slide is marked COLT MFG. CO. HARTFORD CT. U.S.A. It has a serial # of 76xxx. and is blue steel in color. I checked the paperwork that is in the box that it came in, but it doesn't say when it was built. Can anyone tell me where I can find out when this gun was made?