@Sidetrack Erik Cortina interviews Jack Neary series might have the answer for you, here is a link to one of them, but they are all worth a listen: https://www.youtube.com/watch?v=KQsGYONTNps. Your group is a 'four and one' according to Jack. If the groups are consistently like that then he suggests that powder should be reduced two or three tenths of a grain
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