If'n ya get a chance, try some of these!!!
https://www.buffalobore.com/index.ph...uct_list&c=221
Results with my Marlin...
#181 - Buffalo Bore's #44-40-200-HC factory ammunition, Avg. 1,336fps, ES 29, 1 1/4" to 2 1/4" Group @ 100 yards....pressure claims to be below 11,000psi SAAMI
https://www.44winchestercenterfireca...m/buffalo-bore
I have an MGM barrel and a Stevens shotgun I wanted to do the same thing with but it was a bit beyond my paygrade!!!