NH,

I have both in the Marlin lever gun. I have shot buffalo ammo in my .45/70 and it does pack a whallop....about that of the .450.

Three years ago I whacked a coyote with the .45/70. Very littly pelt damage and he never knew what happened. I suspect part of that had to do with bullet selection. I used Barnes X. I think a couple of other posters have said that the .45/70 is easier to find ammo for...I gotta agree with that. I load for everything I have so it doesn't matter much to me, but, I just like to shop around. .45/70 ammo is not only easier to find but it is a bunch cheaper than .450.

hope this helps