I believe the muzzle device is not at fault. Took it out a few hours ago. Shot some, marked the groups shot with muzzle device and ammo type. Removed muzzle device, shot some more, marked the groups without muzzle device and ammo type.
Groups circled in red were shot without the muzzle device. Groups circled in thin black were shot with the muzzle device attached.
Vertical distance from the most obvious POA for each group can be explained by me shifting the holdover for off-topic reasons. Please ignore the variations in vertical distance of each group from what the most obvious point of aim should be.
Attachment 22891