There is a lot of published 6.8 data online from Hogdon, Nosler, Accurate, etc. It will all be safe as no one publishes data for SPEC 2. I have a SPEC 2 AR and a SAAMI spec Ruger Ranch. If are you reloading for hunting deer/hogs within 300 yards, 120 SST, 100/110 Accubond are good bullets that have decent BCs to hold velocity. The 95 TTSX and 110 TSX are also built for 6.8 velocities. The 120 SST is by far the most economical of the ones listed without giving up killing power.