All, happy to report that my switch to a 30:1 Lyman 457125 bullet from Chey Cast Bullets has solved my problem with leading and poor accuracy in my Trapdoor and Peabody!  Was using a 20:1 and getting poor accuracy and leading.  No leading now on the patch, and groups have shrunk to 2.3" with the Trap and 2.4" with the Peabody at 100 yds.  Thanks again for all your responses a few months ago!