02-04-2024, 06:56 AM
Was your resized Grendel brass Starline? If so, you should be very close with the Starline ARC brass - they are made from the same parent blank (Grendel Basic Brass), but you may need to tweak powder a few tenths. If not, you should work it back up again. Starline's Grendel case capacity is different from Hornady, Lapua, etc.
#FJB