There was a member on here who shot that load and gave it good reviews. (TAC/65gr GK)
It seems he said it was around Sierra's book max in the AR-15 section.
I noticed a huge difference using WSR primers with TAC powder. I have no idea why but..... Velocities went up and velocity spreads went down. Accuracy at 100 yards was better. Not way better, but better. And that is better.
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Be consistent with your loading, practice your shooting, speak the truth, love your family and you will be rewarded.