Posted by Jim Stubbendieck on November 6, 2016, 7:27 pm, in reply to "Re: single-sighting rib"
When the single sighting plane rib (SP in the ledgers) was introduced is not clear. The Chronology on this website lists a .410 with a SP that was finished on August 28, 1936. The serial number is listed as 14724. That number must have been entered incorrectly because that number was finished much earlier than 1936.
The earliest finish date with an SP was recorded as March 16, 1939; SN 172642, 20 gauge Field Grade.
Earliest serial number with a SP was 170790 (also a 20 gauge Field Grade), but this shotgun wasn't finished until 1941. Hunter Arms started the shotguns in serial number order, but they were not finished in order. SN 170790 was started on 12/9/38.
Were more finished before 3/16/39 and not recorded? Why would Hunter Arms say they were available in their 1939 catalog/price list and not complete one until March?
If you have a shotgun with a serial number before 172500 and the SP, let us know. I will look up the record to find the start and finish dates. That could help us zero in on when the single sighting plane rib.