Too fast for 20, works in 12. My powder of choice, from light 7/8 ouncers up to 24 gram Bunker loads, all speed one ouncers, light 1 1/8 ounce Trap, up to 1250 foot 1 1/8 ounce Caps loads.
Great all around powder. Extremely clean and easy to ignite, I get the 25 lb "family size" kegs.
This is a bulky, flake powder, the heavier shot loads work best in roomy hulls like Fed GM and similar capacity hulls.