Re: Which factory 308 Win
It is hard to say. It is possible that if your bullet's jackets are not very concentric, you can definatly see accuracy problems running 165's through a 10x. It is less noticable when using bullets that offer very tight tolerences.
It is possible to spin bullets faster than neccesary with good accuracy. Some barrels for what ever reason just do not like a given bullet weight. I dont know why that is, but it happens.
Any time youre struggling to find accuracy you should always try a different bullet. Even if it is a bullet of the same weight but different style. Most likely, you will do better with a heavier bullet or at least match grade bullets.
Try the 175-180's and see if accuracy improves. If not, try 190-200+. You should be able to run 2600 for the 190's and 2500+ FPS for the 200's.
I hope that helps!
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.