My 6.5x06 also prefers lighter bullets. Problem is a 1-9 twist. I think the 6.5x55 military barrel's are a 1-71/2 twist and handle the heavy bullet's very well. My 6.5x55 is a newer mod 70 and handles up to 140 gr bullet's well. No heavier bullet's than that around here. If I wanted to go to 150 gr bullet's I'd go to a 7mm of some kind.
