If you want to follow any number of break-in procedures, fine, Seems like everyone has some of their own, and that's another story. Personally, I shoot a series of one shot, clean, 5 times. Three shots, clean, 5 times. Then on to 5-shot groups, clean. Maybe excessive but it's what I do. As far as fire-forming, as has been stated here before, if you have some unwanted bullets and a reasonable amount of a powder that did not shoot as you had hoped, use them for your fire-forming. I have not had trouble with new brass that I've run thru my resize die, checked for trim length, load as normal, and just go shoot them. Oftentimes, they shoot just as well as the older previous casings. Chamber dimensions can play a role here, but for most intents and purposes, it just isn't going to matter that much, if at all for your intent.