.444 Marlin cases made VERY good. 410's - I've done it.

12.0gr. Unique and 1/2 ounce of whatever you want- I used 6's.

To load:

prime & dump in powder - then thin "B" card wad.

Then .410 plastic wad- push down to powder - mark the side just a tich down from the case mouth - pull it back up a bit with needle-nose pliers, then trim on the line with scissors.

Shove back down and fill with shot to just below the mouth- should be 1/2 ounce- or so.

Then I put a .44 mag gas check cup-down on the shot, then run into the seating/crimp die to put a roll crimp on the case mouth.

Done:

This patterned as well or better in both my daughter's .410's than did any commercial ammo.