Parker Regulation Question

[Theodore LeDurt]

Just got my DH back after a 6 month hiatus for stock work. Early duck shooting made me question the regulation, as no birds shot were centered. Normally I pattern the first week a new gun is purchased, but the stock issue delayed the testing, as the gun arrived the day before the opener.

Anyway, the pattern is 4" high (both barrels ...so probably me), and the left barrel shoots a good 6 inches to the left. My question is, is this in the margin of error? And how much choke (presently .043) needs to be removed to re-regulate? My patterning was done at 25yards. Testing was done offhand as well as on a bench.

Thanks for your help.