What load are you using? I am currently building a 280ai with 26" barrel and want to load 160-168 gr. bullets. Leaning toward 7828ssc due to great accuracy and performance in my standard .280s.Both mine are 26 inchers. 168 grain runs 3015, 180 about 2875. My 7mag was only a little faster with either weight.
I would be thrilled if I can eke out 3000+ fps with the 160 Accubond.