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If the rifle has a good bore with sharp rifling it will be very accurate with good handloads. The groove diameter should be about .379 therefore cast bullets of .380 or .381 will shoot best. Then for reloading, a set of RCBS Cowboy loading dies are necessary. Standard 38-55 or 375 Win. dies will not do the job because they will resize the cast bullet to about .377 which will be inaccurate and lead the barrel.
Best loads are near black powder velocities, 1300 to 1500 fps...high velocities are not needed in this cartridge with cast bullets (I never shoot jacketed bullets in my 38-55s).
21 grains of IMR 4198 under a 240 LaserCast bullet get about 1400 fps and is very accurate. 10 grains of Unique with the same bullet is about 100 feet per second slower but also very accurate.
I don't know what you are asking so I hope this helps.
Jim
Right on the nut.+10 Magnum Man
