Can the .177 cal have the regulator pressure lowered so that the energy is closer to 18 ft-lbs, making it legal for field target (and to get more shots off the regulator)?
Yes, it can be done. Though, you really wouldn't need to. You can likely make all the changes needed via the hammer spring tension adjustment at the back of the action.
On a 3000psi fill, how many shots are regulated on the .177 cal?
If I can only fill the .35 cal version to 3000psi, how many good shots could I expect ?
You get 11 shots on the regulator in 35cal...20 in 30cal...35 in 25cal....it tells you in the description & pyramid air did a review on this gun in 35cal....the only 2 shots n fall off the regulator, the guy who said that as an answer isn't correct at all
The regulator is set around 170 BAR, so you would only get about two good shots before it falls off of the regulator. The lower caliber regulators are set lower and would yield more shots.