I have had exellent results from the 30-20 and 32 H&R mag on big bore silhouettes using the RCBS 175gr. bore riding silhouette bullet and either WC820 or WC680. Both like rifle primers, and will work well around the 1300 fps you'll want to get to take the rams. Of the two, the 680 is more forgiving and you'll get better case life using it. You can also do this with either of the 4227s, AA1680, 2015, WW296, or H110. Charge weights for the pistol powders (296, 820, or 110) are around 9-11gr, and the rifle powders around 13-14gr, though you'll need to chrono individual loads in your gun to get it where you like it. Just start light and work up, and watch for sticky extraction. With some experimentation you'll find that's one of the best, most versatile barrels TC ever made.