Do you anneal your brass? I wonder if that would make a more consistent neck to bullet tension? I have went to a factory crimp die for my 35 Remington. I did that for other reasons but an unknown benefit was it really tightened up my 3 shot groups.
I started with a Lee Turret 35 years ago. Switched to the Co-ax about 20 years ago for all my rifle loads and never looked back. I still use the Lee for my pistol loads but not any precision rifle loads.