Where you shooting a group as well, or just into a trap for velocity numbers?
Honestly at 30 yards if your pellets are all hitting the same hole you will be fine. Could play with the hammer spring a little and see what happens, though I would back mine off and shoot again. Though I am far from an expert on the tuning side, but the numbers seem to be all over the place at times. Low of 850 to a high of 963 so over 100 fps change.