The 45/70 just plain WORKS. The current arms on hand are a Bubba'ed TD that I will get around to some level of restoration upon--Buffington sight and all--and a Marlin 1895 that is definitely a Wednesday-made rifle. .459" Lee 405s stack one on top of the other at 50 yards and threaten 1.5" at 100 yards.
I have TD-level loads assembled as follows--WW cases primed with Fed #215. 6.0 grains of IMR-4198 next to the primer, then 48.0 grains of WC-860. Seat the Lee 405 with a bit of powder compression to keep things stacked properly, and sally forth. This has been my go-to 45/70 TD-level load since the late 1990s. In a good rifle, it will print 1.25" to 1.5"groups at 100 yards, and not beat the daylights out of you from the bench. In my misspent youth, I was fond of running Hornady 350s at 2000-2100 FPS through my Ruger #1, but in the fullness of time better sense finally dawned upon me and Bret's assessment one post north became canon.
About that same time, it occurred to me that the S&W Model 29/629 revolvers weren't the best choice for full-tilt hand-cannon recreation. Cast Keith SWCs at 900-950 FPS make a lot more sense (and can be enjoyed rather than endured while discharging them).
We grow too soon old and too late smart.