Posted by Tom Martin on December 8, 2013, 11:45 am, in reply to "L.C. Smith "O" frame"
There is no "0" frame. The frame sizes were Regular and Featherweight. The "0" is a grade marking for the next to lowest grade gun. A regular frame 0 grade could be 10, 12 or 16 gauge regular frame until 1913, and could be 12, 16 or 20 gauge FW between 1907 and 19i3. the dimensions are different between the Regular frame and the FW frame, and will have more minor variations between the gauges within the grade. You will have to be more specific in your description to get a usable forend.