I have never been able to get either 178 bthp or ELD to shoot well in both 308s I have. That's just me though, I will echo other recommendations to stick with Sierra or Berger.
Guys like Rangers or SF never ended up with leupolds that Horus reticle in them on the 110/SR25? I know they started training with Accuracy 1st at some point.
Those CTR mags are butter smooth, are shorter and still hold ten. Plus I think all factory tikka stuff looks really good together. Longer COAL in the CTR as well. I may try an AI mag, which brand are you using?