You need to have the gun evaluated, especially barrel wall thickness. If they've been honed too thin, it's unsafe to shoot. If everything checks out, it's fine for CASS using the appropriate loads.
As DocDrew mentioned, it was probably "KAD", the "D" indicating the barrels are Damascus. If the second letter had been an "E", it would have ejectors instead of an extractor. 1900s with fluid steel tubes typically have a "Y" letter. (As in Skeettx's picture) For example, a "KEY" gun has ejectors and fluid steel tubes, a "KED" with ejectors and Damascus tubes.
Regards
Ken
Last edited by Ken61; 04/10/17 10:40 AM.