Originally Posted by Timber338
What brass are you using? Check your neck thickness with a good caliper and make sure all individual brass has a neck thickness variation .002" or smaller. .001" is better.
Consistent neck tension on the bullet is critical to getting great groups and small Extreme Spread. If there are large variations it doesn't matter what powder you use you won't get the results you want.
I just started using Lee Collet dies for it. And measured the neck, they weren't that tight but they were within .005 of each other. The brass I'm using at the moment is remington. It seems to be ok, but I may throw down more money for the next batch. What brass would you suggest? I've heard good things about Norma, and Lapua?