Posted by David Williamson on January 18, 2015, 6:22 am, in reply to "Factory bore diameter"
Tom, at the time of the Syracuse guns 1880-1888-89 I don't think there was a standard bore diameter. I have measured a few and the one 12 gauge I have from 1887 that was honed is now .743. I know it was honed because the bores are very shiny.
In Brophy's book "L.C. Smith Shotguns" he gives a standard of .729 for 12 gauge and I have measured quite a few of the early hammer guns that were from .725-729. Most of the hammerless were .729. Later production shows bores from .729-.732. I have not seen any higher than that and would presume if higher that they were honed.