I recently acquired a WR detachable lock 12 bore "one" trigger. It is unusual in that each barrel was stamped with a different serial number, one matched the number on the trigger guard and the other, a much later number, did not so I sent 60 to WR and a week later I got back an authentication certificate, a historical letter and copies of their ledgers detailing both serial numbers. Seems that the original gun was delivered in 1912 for a Percy Hobbs Esq. with 30" steel tubes. It was sent back to be fitted with new 28" steel tubes in 1984 for an Ivan Babaya. I didn't know that new serial numbers are placed on replacement barrels. New barrels did not have an address on the rib just Westley Richards on one barrel and England on the other. It has game scene engraving not the usual scroll.