Fisher.......I am going to look your load up indeed! I just picked up my Hodgdon manual dated 1979 and low and behold they do have the 45/70 load listed but here is what they say on page 185 of that manual.
45/70 HEAVY LOADS FOR RUGER OR MARLIN 45/70 ONLY!
300 Grain Bullet, Powder H-4198 at 52 grains, Velocity 2123fps.
300 Grain Bullet, Powder H-322 at 60 grains, Velocity 1965fps.
It just strikes me a little funny that your telling me that Hodgdon states you can do this and my manual says different but so does Hornady's new manual and Nosler Manual also. Something just doesn't sound like everything with your load listed is spot on mate.
I will have to do some further checking on this high velocity load and powder amount. So far I have 6 reloading manuals that say your load far exceeds safety measures.
