Thanks for posting the pics

The picture on the left has a much more uniform distribution of pellets than the one on the right. I certainly cannot argue with the number of vital hits however.

The easiest way to improve that patter, should you desire to do so, is move to Hevi-shot 2oz #6. The choke you have is pretty tight, maybe too tight for Hevishot but you may get away with it using smaller shot sizes like #6 or #7.

It is possible that the .655 is overconstricting the lead loads you are shooting and you may get better patterns with a more open choke - without a larger target it is hard to tell.

Good luck

MC