Im new to the 45/70 but love it.
I dont think the +P loads are necessary but each to their own. They will kick a bit.
Lastnight i was shooting a gong out at 200yds with the 350gr Hornady RN @ 1950fps no worries then tried the 325gr FTX out to 360yds, again it went good.
My 350gr hardcast load gives me a cheaper practice bullet while shooting the same poi as the 350gr RN.
Let us know how the Grizzly loads go for you
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