HPA regulator lag

[SuperNova]

hi all
I'm getting a bit of Regulator lag. My first shot will be bang on the psi, but the others after it dip significantly then settle. after shooting the pressure builds up again
I've got a ninja lpr v2, a valken boy 48ci 3000 psi tank and an amped wide bore line.
I have read up that you can reduce the output pressure of a tank by removing the head, and taking out a certain amount of shims.
Would i be right in saying that if i were to remove all the shims from the tank, it would put less stress on the regulator, therefore increasing response time?
Thanks-
Joe