The 12 in the diamond is a pre-1924 mark. The Date of Proof letters started in 1922.
18.4 is the bore in mm 22 cm from the breech = .724"
17.8 is the choke = .701"
The 1 K xxx is the barrel weight after smokeless proof
The spangled letters are controller's (inspector's) marks

Last edited by revdocdrew; 11/19/08 05:25 PM.
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