FX Impact MK2 Regualtor

I have an FX impact MK 2 and recently changed the barrel from .22 to .177 to try a Polo mint challenge at 20 Mtrs as most guys are more accurate when shooting with .177… on changing the barrel I can’t believe the inconsistency of grouping and tried JSB Diablos and Snow peak .177 slugs.. to cut a long story short for a gun Like an FX zeroing it in at 12 Mtr the power was dropping constantly but the pressure was 200 so all ok there..

on looking at the Regulator it’s down to almost zero and trying to utube how to put the pressure up … any tips before I take my Gat to bits LOL
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