Please look at BL1 and BL2 on the proof chart

https://www.vintageguns.co.uk/articles/proof-sizes/

http://www.hallowellco.com/bore_size_chart.htm

If can make out the original date code, that would
be of help

Mike

Last edited by skeettx; 11/23/18 07:55 PM.

USAF RET 1971-95 [Linked Image from jpgbox.com]