i've been reloading the 6mm ARC for awhile now. i'm using a wilson bushing die to convert 6.5 Grendel Brass to 6mm ARC. I'm on my 3rd reloads on the Hornady Brass, 2 on Starline Brass. And just converted the Grendel Lapua Brass. Have not had any issues. Both for Bolt Action and Gas Gun.