45man, you might try a fired 45acp case this would allow an extra large projectile in the mix, I?ve read where folks have fired them in 475?s.
I?ve always had good luck with leather and a drop of Elmer?s......I make shot for my 500?s.

Trapr


NRA Endowment mbr.
USPSA/IPSC
U.S. Practical rifle/shotgun national team