Fill pressure poi question

I would say yes and no. Depends on your particular gun as not all of them are equal nor shoot equally well. 200psi is miniscule considering over 4000psi you should get at least 3 dead on shots unless you start with valve lock.

HA

Posted by: Savoyspecial

If I change my fill pressure on a extreme big bore from 4000 to 4200 will my poi change at 50 out to 100 yards? 

Well, as a class of airguns, "extreme bigbores" tend to prioritize MV over other considerations, which in extreme cases can make muzzle energy nearly proportional to fill pressure.  If that's the case with your biggy, 4200/4000 = 5% more PSI may (nearly) equate to 5% more muzzle energy, and therefore 5% less drop from boreline at any given range.

At 100yds, guessing at an MV ~900fps at 4000psi, that could (note emphasis on the guesswork factor) imply as much as an inch (~1MOA) higher point of impact.

Your mileage may vary.

Thanks guys. Sighting in these big bores can be a pain. Filling that high can start running out of high enough pressure to get it zeroed I’m in my big tank.