The charts above in essence say this, JSG stick have a Standard deviation of 200, whereas the 777 pellets have a standard deviation of 23. If you go from 2 pellets to 3 pellets, usually it only makes a 400 fps difference. JSG stick are 200 FPS off from shoot to shot, that is huge in my mind---1/2 a pellet or 25g of powder. Values less than 40-50 fps are what I would expect, most other powders are below that value. If the JSG sticks and the APP sticks are that far off, I would not use them. The loose JSG and APP seem to be more consistent, but NOT as consistent as 777, which improves accuracy shot to shot, and that is what your trying to do, every thing consistent---powder, loading pressure, sabot, bullet weight, primer charge, every little thing makes a difference---shoot a loose sabot vs a tight sabot and accuracy suffers, shoot a Kleenbore primer vs a Federal Primer in a Savage and you have misfires, shoot an inconsistent powder and expect spread in your shots,etc.
Chap Gleason