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troopcom · October 14, 2011, 11:54 AM

Looking at a M91/30 with a "OP" proof mark on the receiver and also a single "P" on the receiver, dated 1928. Can anyone tell me what this mark is and means?

October 14, 2011, 11:54 AM	#1
troopcom Senior Member Join Date: June 24, 2011 Posts: 230	Help to identify a proof mark Looking at a M91/30 with a "OP" proof mark on the receiver and also a single "P" on the receiver, dated 1928. Can anyone tell me what this mark is and means?