The round was originally designed for black powder. If you down load your ammo you may have some problems with certain powders being position sensitive. The 45-70 still has quite a following and the powder companies have provided several powders that will perform quite well in this old large round. I have a Marlin 1895 and all I use are cast bullets in it. 99% are my own cast bullets. I have had the greatest success with 405 gr cast bullets using Accurate 5744 or H4198 in it. If you don't load barn burner loads the brass will last a looooooooooong time. I'm still using the original brass that I purchased when I acquired the gun in 2006.
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