Anyone here do concentricity checks on their AR ammo? My 6ARC seems to be doing a number on the case necks. Bolt gun brass less than .001, 6 ARC .005. The cases are old Hornady 6.5 Grendel brass I formed into 6 ARC. I am using a Hornady FL die with expander removed then expanding to .240 with a mandrel, same procedure I use with bolt gun ammo. This one has me scratching my head