I have a 270 wsm, I started 140 grain accubond load development with the book RL 26 starting load, got max load velocity and stopped right there. Fast velocity is a pressure sign. If you don't have pressure testing equipment a chronograph is the next best thing. I always try to stay within book velocity with my loads, as you gain very little by exceeding them. You only get to blow your damn head off one time.

"Before you criticize someone, walk a mile in their shoes. That way, you'll be a mile from them, and you'll have their shoes."