Can't answer your question, but thanks for the info. I've been using the plain FC brass for my match grade 9mm loads, and it has been very consistent. I didn't use the .FC. brass because I didn't know what it was.
For plinking/practice I don't think it would do any harm to mix them, people use mixed head stamps all the time with 9mm, and the two varieties of FC brass are probably closer to each other than mixed brands.
Last edited by Hammerhead; October 10, 2011 at 02:49 PM.