I bought a real nice slightly used 18-3 back in '89 from an FFL friend when I lived in NJ. The receipt shows it's an 18-3.
I always figured that they need to make up some 18's and used available 17 frames.
Here is a photo of the over stamp model #. Maybe 15 years ago I called S&W to ask about the over stamp and if my gun was an 18 or 17 and any other info. The woman that I spoke with replied, "I couldn't tell you." I asked if it could be determined by the serial #. She wasn't able to check. ?????
I gave up at that point and have always called it an 18-3.
