Interesting, the description and photo are both indicating case failure much closer to the neck, farther from the head, than I have previously seen described. The typical area I hear referenced is only about 1/4" above extractor groove.
That picture looks a lot like what my Lee Deburring tool does to cases.
Still happily answering to the call-sign Peetza.
You do not HAVE a soul. You ARE a soul. You HAVE a body.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.