Airgun Technologies .25 Uragan 2 700mm regulator adjustments results?

Have any of you tinkerers been recording power levels/shot count on different regulator settings?
Mine is factory, shooting 33gr Zans at 975-ish. I'm wondering what velocity/shot count I can expect at lower reg levels. For example, if I settle on 60fpe, how many shots can I expect?

I'd play with it myself, but I fill it by hand pump. Normally I don't mind, but draining the whole bottle just to experiment seems counterproductive, so I figure I'd ask on the forum. Thanks.