Its been a very long time since I reloaded 20ga shot shells with my old Mec 650.

I used to use Hercules Unique powder with good results. I think its called Alliant Unique now.


[Linked Image from i.postimg.cc]

I copied this from an article on line

Alliant's Cleaner-Burning Unique Powder
by Jeff Quinn



Alliant Powder Company is manufacturing a cleaner-burning version of the old Hercules Powder Company's Unique powder. The new powder is shown here (on the left) alongside some of the last of the author's stash of the old Hercules Unique.