This load was posted in the First Accurate manual,

58gr's AA3100
Win case
150gr Sierra bt
Federal benchrest primer

In my M98 Mauser 24" Santa Barbara action& barrel, Bell&Carlson stock it makes 3109fps across the chrono. 3 shot's in .4in at 100yds.

For an easy to load, all around .270 I use 53.5gr's H414, win case cci250 130gr Ballistic tip, 3100fps, groups under 1/2 in 3 different rifles.

GSF1200,

I suspect that you have a very fast barrel. I can't get anywhere near that velocity with my .270, which seems to me to have a quite slow barrel.