I have a Smith&Wesson Model 57 4" barrelled revolver in blue finish. Bearing serial no N691614 and Mod 57 on the frame I am wondering when it was made. It has a pinned barrel and recessed chambers and appears shot very little. It came from a New Old Stock supply of a closed down sporting goods store in Vegas. It came in the original box with cleaning rod, slotted tip and a brush tip and the correct serial on the box.

That would be 1980