What powder to copy the Hornady 123gr AMAX? What else would I need to do?

[elfego baca]

I have tried two powders in my Grendel. The first was AA2230. Accuracy was ok but velocity was mediocre. I switched to AA2520 and get nearly 2500 ft/sec with 123 grain bullets either Sierra's HPBT or Hornady's A max out of a 24" barrel.