I should have asked earlier. What kind of loading gear do you have? Loading black powder is a total abdication of loading smokeless. You need a drop tube, compression die, and wads or a wad cutter on top of the usual tools for smokeless.
With a little research, I’ve never found it that hard to get any of mine to shoot well.
1. Size and prime case (some friends of mine don’t size once fire formed, and that’s fine too)
2. Bell case mouth(only if you size the case).
3. Weigh/throw powder charge.
4. Trickle power though drop tube at a steady pace for uniform compaction and column height.
5. Insert over powder wad (can be made from almost anything I prefer veggie fibre .030” thick)
6. Compress powder to the depth of full seated bullet.
7. Seat pre-lubed bullet and removed bell from case mouth.
8. Chamber round, hold centre and send it.
9. De-prime brass, soak in hot soapy water, then wet tumble in ceramic media.
10. Let dry.
11. Ask yourself why you didn’t do this sooner in life, then purchase another BPCR.
12. Wonder why your bank account is drained.
13. Start back at step 1.