45-70 is a sweetheart to reload... very tolerant... mine shoots most any old load pretty good... and a couple hotrod loads very, very tight indeed. I'm not going to presume to recommend a specific load to you, but will say I've had good luck following the common wisdom that dictates beginning the loads with a couple grains less than max and CAREFULLY working up from there. Have fun! ///olde 8) pharte///
Many manuals list two or three pressure levels for the .45-70 Government cartridge. You must absolutely know what pressure levels your firearm is rated for. A hot load in a not so strong action could ruin your week.
I have to keep things on the mild side for my 1873 Springfield. Accurate 5744 with 405gr lead bullets works great.