Ok I needed to confirm to leave no doubt in my mind. So I fine tuned the load in with a slight change of Charge weight. Same powder lot. Same primer lot, same bullet lot.
Went from 82 gr to 82.2 gr and it tightened up. If I don't blow it , it will shoot .25 moa. And first round from a cold barrel is dead nuts center aim point. So, after all this I called it done. Now I needed to revisit the chronograph to see what increase in velocity I got with an additional .2 gr. In fire formed brass, 82.2 gr is shooting 3100 fps again with single digit ES.
Bottom line.
Virgin brass with 84 gr = 3100 fps.
Fire formed brass with 82.2 gr = 3100 fps.
1.8 gr less charge, same velocity.
Velocity from a proven Magneto speed I have learned to trust.
Jeff