But how is that any different when done in two steps as opposed to in one? You are still gonna try and crimp above the cannelure. If you dies are set-up correctly, you are not going to have enough bullet travel when the crimp starts to deform the brass. At least not enough to go past the whole cannelure. If those cases are that long you get a crushed case doing it in one step, odds are you are going to get a bulged case in two. That brass too has to go somewhere. It goes out instead of down. Your final crimp is to the center of the cannelure, this gives you a margin of error. If you need more than that, you probably need to be more selective of your brass, or ease up on your crimp. For you boys with a progressive and enough stations, two steps is no more steps. Not so much for a SS. Again for heavy for caliber, or heavy recoiling loads in longer cases, there is a chance of crushing a case. In .357 and using a SS where you need another stroke for each round, the minuscule risk of a crushed case is well worth it when it comes to thousands of rounds. At least in my book.
