I agree with Lou tht if you want more velocity out of a 270 put a 24" bbl on it. My Rem 700 gets 3180 consistently w/ 130 Accubonds and sub MOA (61 gr. H4831) Granted, it's a warm load but I don't have to AI.
All that said, I'm in the middle of building a 280AI sheep rifle. Seems like an ideal balance of rifle weight, shootability,
velocity etc.
just my .02.
sbsmith
