I don't think anyone is belittling anyone here intentionally...back to the topic... Two of the three procedures being discussed here are advanced tactics for reloading and one, chamferring is pretty basic. TO be honest, with a factory chambered rifle, inside/outside neck reamming are not needed and will produce very little of anything other than if you take to much off, you'll cause greater space between the neck of the cartridge and chamber, usually resulting, if the stretch is to much-- a cracked neck.. I believe you may have a chamber that may be too big, if your cracking cases on first firings..it all depends how many chambers were cut with that reamer at the factory, the first ones seem to have the problem more so than the later ones... WHAT is the measurement of a fired case neck..check the reloading manuels and see what a sized case should be.. subtract the difference and see how much yours are expanding.. I'll bet it's more than .012, if it's much more than that I'd say that your problem, not the cases but the expansion...