So, just to chuck a variable into the equation that hasn't been factored in - what affect if any would adjusting the seating depth of the projectile deeper in the two loads you've selected for the second round of the testing have?
Noting that you've settled on magazine length for the seating depth which is fair as most would either do that or set their length to the "book length" and forget it, yet seating deeper by a nominal amount is what some pundits recommend as a final step in tuning the load...
Would be a rather interesting final comparison just to check what difference if any this adjustment would have on your data.
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