CAN I SHOOT SLUGS ACCURATELY OUT OF THE FX STX PELLET LINER A?

Has anyone tried this with 500mm barrels? 



I've been toying around with different settings on a new impact compact. 22 



Currently to enjoy the short 25 inches and not be loud I've got it tuned at about 75 bar reg...



Getting about 830fps on power level 3...876 on max... with jsb 18.1 ... that's about max fps for keeping it somewhat quiet without adding a DonnyFL yet. 



I'd be interested in trying the NSA 17 and seeing if I could get useful results without having to increase the reg.