Contact Bob Beach at Griffin & Howe. G&H hold the records for Von Lengerke & Detmold and Abercrombie & Fitch. Those two firms imported many of the Greifelt guns that were brought into the U.S. There is an inquiry page at the G&H website where you can check the serial number, however with my Greifelt it did not show up when I did an inquiry, but Mr. Beach found it right away when I called him. If the gun is in their database you can purchase the inventory records which will include a summary of the original specs on the gun, date of import, etc.
Last edited by steve f; 01/13/19 11:04 PM.