I got to wonder where you came up with the conclusion that app "sucks". We tested all the powders side by side(before blackhorn came out) and it performed just dandy. We cronographed all loads,accuracy tested,glued strain gauges to the sides of barrels,shot at white paper at close range and everything. The only fault we found with jim shocky select was if left exposed to moisture very long it would clump up.
ORIGINAL: FG
APP sucks.
Get either some pyrodex,triple 7 or as u said, blackhorn.
The sabots could also be an issue but take one thing at a time.