I purchased a Mauser that has been barreled to 270/308Ackley. A nice set of Redding dies came with the rifle. I bought 250 once fired 308LC cases. They have been resized(308). I felt it would simply be a matter of running the 308's thru the full length die. I promptly shoved the neck into the top of the cases. I kept adjusting the dies up. After destroying 6 cases here I am! I have been reloading for a year or so. Never for a wildcat. Would some of you reloaders who are experienced in case forming have an idea of what I might be doing wrong?