Re: Iver Johnson Champion Receiver
there are no known serial number records for iver johnson single barrel shotguns, however my research has shown the serial numbers with a single letter suffix were usually manufactured in the mid to late 1920. during that time there was only one frame manufactured for the different gauges iver johnson offered. the small frame champion model 39 was discontined about 1919. most of the popular gauges were offered, 410, 20, 16 & 12 along with limited production of the 24, 28 and 32 gauges. the barrels easiest to find would be the 16 and 12 with 410 a close third.
iver johnson was issued a patent in 1915 for the addition of metal to the bottom of the chamber area on single barrels that allowed the use of small bore barrels on a standard size frame.