Small rifle primer adapters

[bruce moulds]

most interesting brian.
you have saved me doing the same experiment. i always wondered about this issue.
shooting in a bit of condition as you were, there is little point in worrying about too much horizontal.
statistically there is probably insufficient evidence to say the 1/2" vert group is better than the 3/4" or even 7/8".
what you can say is that they all shoot under 1 moa, and one might be better one day and another the next. it is now time to compare aggregate group sizes.
all groups seem accurate and well shot with large primers.
in actual practice the easiest solution is to just load br2.
keep safe,
bruce.