I use H4198 behind a 405 gr. Remington, somewhere around 47.5 grains gives 1,861 fps from my 22" inch barrel. This load is fast enough, very accurate, and gives no pressure problems IN MY RIFLE! I think IMR-4198 is a little faster so you should find specific load info for it. Pretty good powder for the .45-70 IMHO.

Every normal man must be tempted, at times, to spit on his hands, hoist the black flag, and begin slitting throats.