I have been a member several years and have been collecting other milsurps / C&Rs for 25 + years. a little over 5 years ago I changed direction of my collecting to Single-shot rifles and have assembled quite a few nice pieces. I have learned much here and by the ref book by Marcot and Laymon. Now I need some help. I aquired a custom Martini, looks like a German or maybe Swiss build. Quite a nice rifle but I am curious as to the builder, and of course the cal. the seller just stated it was 40-77 with nno reason for that assumption. I will attach pic in my next thread. Any help will be appreciated.