Try Remington Core Lokt Pointed Soft Point 130gn ammunition - it's the only really accurate factory ammo I've found for my .270 and two others I load for. The cheap PPu stuff was appalling but the expensive Norma and RWS stuff wasn't a lot better!
In general, the .270 seems to prefer much longer rounds than the standard factory length, hence the difficulty in finding accurate ready rolled loads - my home loads with both BTs and SPs are way longer than standard, with the bullet just seated to calibre depth (i.e. 0.277")
Adam.