From what I've seen of most hammer guns, it would be straight forwards to retrofit a safety on the upper tang similar to the safety most (American) hammerless models have with a simple slide to block the triggers.
It's something I'd consider doing if I had the machining equipment (and was experienced at using it).
Steve

Last edited by Rockdoc; 02/03/12 07:51 AM.
Approach life like you do a yellow light - RUN IT! (Gail T.)