I have a .45-70 like the one pictured, also a .458 Win Mag
Ruger also made about 250 of them in .450 Nitro, for a limited run. They had C weight barrels (like your .45-70) except 26" instead of 22" long, and they had Circassian walnut (usually plain, though).
In the #1 it's quite versatile, since as Jorge said you can duplicate blackpowder loads, or you can load up past factory .450 Nitro loads, in the strong Ruger action.
There is a huge variety of bullets available in that bore size, and the Ruger can use about any of them, within reason. Nosler and Barnes both have pointed 300 gr bullets, that have potential to shoot fairly flat, it that's of value to you.
That rifle is a compact powerhouse
