That’s an excellent concern, Ted. I’m undecided. Here's a pair examples of what I’ve heard in different spots on the Federal 210 vs Federal 210M variances: I have been reloading for more than 35 a long time and possess routinely switched among Winchester, CCI and Federal ( I buy regardless https://federal-ammunition-primer57890.wizzardsblog.com/31805453/federal-large-magnum-primers-an-overview