I can find very little data using H335 in the 45-70. I have all the manals. 49.0 grains of Varget will yield 1591 FPS as a starting load and 55.0 grains Max for 1772. Also IMR 4198 and H322 will work well. These loads are from the new Lyman Manual. This is the BIBLE for cast bullets and has good loads for jacketed bullets as well.