Hello Nailcreek,

Very nice rifle. Love those Martini sporters, just great. Have you confirmed the chambering ???? While 577/450 is surely a popular one it is far from the only one. I have seen 2 Rawbone's over the years and both where 450 Musket No.2. Just a first thought. I have not seen any report of bore condotion ??? If it is good then most any changes there are nearly criminal. Maybe line it to something or rebore to a 577/500 or ???????????

Very nice gun, enjoy and love it.