My Airsporter S is well done on power, I have fitted a new standard spring, O ring, buffer washer and lubed everything, all from Chambers so no dubious parts still only 8.5 pounds up from 6.5. I have put 250 pellets through it but has reached its max, should be possible to get more I'm sure, but having seen a mod on here ref T R Robb removing the buffer washer to long stroke it by the thickness of the washer. Could the piston be put in a lath and a similar amount be taken off the face and radius-ed to do the same thing, i.e, slightly longer stroke. Having read the posts about OX and Titan springs being too harsh on firing don't want to go down that road, however would like to get it up to 11.5, tap is good, but cant remember whether there is enough up the front of the piston to do a similar mod, has anyone removed the buffer washer with no issues etc. Any other tweaks I can do rather than stronger spring, have re-tuned HW 35 HW 77 before so took my time on the BSA, no leaks from tap and using RWS super-domes as advised on here. deerwarden