PA 24,
I have sent pics of the checkering to Jay. Perhaps he will post same for your expert opinion, as I don't have a gauge.
An observation--- you seem to have a vast knowledge of the subject of Smiths, apparently obtained from studying Brophy and Houchin's books. This may come as a revelation to you, but BOTH publications contain a number of errors and many have been noted by those of us who concentrate on Smiths. Futher, Grade 5's were made to order-- for example, the serrated triggers on my gun. Finally, those of us who collect Smiths have a saying--- "Never say never"
I don't appreciate your BS comment---that was uncalled-for when I was trying to help another poster.
Dick Miller