Marauder Pistol

[Nutcracker]

What fps would produce the most accurate groups with a 15.89 JSB? Or would a lighter pellet than that be more accurate?

The last adjustment I did was 5 3/4 HS. 1.5 HT , 3000 PSI Fill. 15.89 JSB ( I was using the 18.1 grains, but think they may be to heavy)
700 722 710 712 722 727 725 745 751 (2700) 759 762 763 772 771 749 (2500) 762 753 761 757 757 759 754 760 759 750 759 (1900)748 742 743 738 737 724.
I did all of this with the AR stock off, when I put the stock on and was sighting in, I noticed "sputtering" @ 1900 psi.

Think I am going to back things off a little and try to get more consistency and see how the accuracy is there, worry about more energy later.