That is the almost the load I shoot. 8.1grns of Unique, 200 grms .427 cast bullet from a local manufacturer. I never get that accuracy from my Navy Arms Uberti 44-40 7.5 barrel. I was wondering if it could be 44spc barrel vs the 44-40 barrel. I was surprised to learn from looking at the Cimarron chart that the barrel bore for 44spc is smaller than the 44-40.
CAL. .44 S&W SPC 20"(508) RH .417(10.59) .429(10.90) 6 .1076(2.73)
CAL..44-40 20"(508) RH .4215(10.7) .429(10.90) 6 .1327(3.37)
My reloading manuals Lyman 1967, 2002 have bullet size for 44-40 .427, and .43 for 44spc could .0045 make the difference. I always thought that the bore of the 44-40 was smaller than the 44spc. Should I be getting a 44spc with a 44-40 cylinder. I have been doing the opposite for years, getting a 44-40 with a extra 44spc cylinder.