We went at it a bit different we used power piston wit the appropriate amount of shot with a wad of paper to hold it in place with 50 grains of 2F black in the 45 and 6o in the 54, we managed to break hand thrown trap at 20 yards regularly. This was before the inlines came about and was with slow twist PRB barrels if I remember correctly the twist was 1 in 80.