Good point. Funny now you mention it I have a Walther Dominator 1250 with the same issue. Had the reg looked at and fills ok, but hammer doesn't release it properly so shoots in the low 500's
Will have a play with mine and see if beefing up the hammer spring will overcome the reg issue and fire - but assume it will be well over legal limit if it is as you say overfilling the reg.
Still learning in this game. Good luck with sorting yours
FTP900 +Sightron S111 10-50 x 55
AA Pro Target in FWB FP70 stock + MTC Mamba lite
Daystate Airwolf + Bushnell Elite 6500
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