You are aware that the 45 ACP has a maximum range of over 2,000 yds, right? And it is capable of harassing fire at 1,000 yds.
If you want range from your 45-70, slow the MV down and up the slug weight. 450 to 500 grain bullet will take down any animal that walks the earth, unlike your Hornady load.
I have a Colt .45 series 80, why don't you go talk to yourself, you can't possibly know what you're talking about. Let's see, 2,000 yards = 6,000feet from a slow knock down round, and a hand gun no less LOL.