Never to hijack this thread but a buddy of mine that produces ammunition indicates the Federal 210M primer. Why, I don't know as he was attempting not to give me proprietary information. I will utilize the Lee Hand Priming Instrument Once i get all-around to using the Feds. Ken, the https://trentonubytn.ampedpages.com/detailed-notes-on-federal-primers-large-pistol-59024079