Originally Posted by rich
The instantaneous pressure in a springer, at the moment the pellet "lets go" of its hold in the breech, can easily be several hundred bar.
According to what I read from Cardew & Cardew in The Airgun from trigger to Muzzle at page 31 the measured maximum peak pressure in a 12 fpe non dieseling springer is only 1366 psi or 94 Bar.
(go here for free download: http://www.mediafire.com/download/5m...o+Muzzle_s.pdf
That is only a little bit more than the regulated pressure from a 12fpe PCP (usually 75 to 90 Bar).
So my guess would still be that the relativley heavy springer piston moves slower and builds the pressure more gradually than the light and fast opening valve from a PCP.
Does anyone know to what pressure Jon Harris sets the regulators on the rifles he tunes and converts? If he sets it to say 110 bar I would say the theory from Rich holds. If he sets them low, with higher volume I guess the springers also build there pressure more gradual.
It also seems more logical to me that a less blown up pellet has lower drag and bucks the wind better. But maybe I'm wrong?