Since R.L. Wilson went out of the picture Colt's don't seem to be interested in outside researchers. Instead they would rather sell the information. If you call their Customer Service Department at (800) 962-2658 and give them the model and serial number they'll tell you the year it was made, and nothing more. The person you're talking with will be reading off a computer screen and may or may not have any in-depth knowledge of the subject.