That seems an awful lot of shift at 7 yards. I didn't need to adjust either my Walter P22 (Gemtech P22 to 1/2x28 adapter, iron sights) or Ruger 22/45 (factory threaded barrel, red dot) shooting steel plates at 10 yards. Since the plates need to be hit in the top third to fall any significant POA/POI shift would be obvious.
I'm having bit of trouble getting my head around the need here -- carrying a can of compressed air and a suppressed pistol "to be as discreet as possible" doesn't seem to match up with the "for all lawful purposes" we tend to put on the paperwork. What exactly is this "need"?
As I've said I've never noticed any first second shot differences with my Sparrow simply because the noise of the bullet hitting anything substantial masks it. Maybe next time out I'll intentionally put the first two rounds into the soft dirt that piles up below the plates to see if I can notice any difference, hitting the plates or the hard packed dirt around them clearly masks any first round pop where I shoot.