Hogwash. Every reference table i just looked at has 12 gauge bores at 18.5mm. EXTREME overbores can get up to 20mm. Is the CSSA suggesting the portion threaded at the end of the barrel for the choke insertion (which would be slightly larger) is the 'bore' for measurement purposes?
I'm all for being cautious. But really?
I'm all for being cautious. But really?





















































