You can probably work up good loads with several of the powders you have. W748 is probably the one I'd start with except that I just checked Western's new data for AA 2520 and they loaded with the FTX. You can download the new Western Powder #5 load guide at either the Accurate or Ramshot websites and you can request a printed copy as well. TAC would be another great choice if you had it. If I were you I'd probably build loads with both 748 and 2520 to see which is most accurate at the peformance level you want.