There was a family here, dad, mom, and two boys, who used 9.0 Red Dot for many years - you could actually see the shot ball going downrange. Maybe he finally got a wad stuck, because he eventually bumped it up to 10.0 grains. I've settled on 12.0 grains Red Dot with 7/8 oz shot and a Windjammer wad. If the crimp collapses in due to the shot column not being high enough, I use a piece of plastic packing peanut on top.
10.5 grains of Unique? That's not a typo?