Drew and Researcher,

Thank you. I just picked up a 1917 Flues 12 ga. marked 2 and 4 which should mean mod and full. The gun appears unmolested. Both bores measure at .717. Right choke measures .712 and left .695 so more like skeet 1 and mod. I found an Ithaca-source chart in Shotguns by Keith that says full is .693 and mod .711 very close to what I measured but the chart is based on a.729 bore. Any thoughts?