Crimp problem; destroying shell

[vujade]

What is causing this and how do I fix it?  

I'm using a Dillon 550.  Seating die in station 3 only seats the bullet.  I have a Lee Factory Crimp die in station 4.   Everything is perfect until the 4th station where I feel the case buckle.  I reseated the crimp die.  I put a good round in there, raise a dummy round and screw in the die until it makes contact.  Lower the dummy round and turn in 1/4 of a turn.  I raise it up, no issue; very slight crimp but not enough to hold the bullet well (I'm able to push hard and lower the bullet).  I screw in the crimp die 1/8 of a turn; and what you see below is what I get.  I've tried several cases including new never fired cases. 

I must have loaded several thousand rounds of 223 by now and this is the first I've seen this.  I did not make any drastic changes.  In fact, prior to this, I was had loaded about 20 perfect rounds.  

 

Edited November 28, 2019 by vujade
(added photo)

[RED333]

Bad brass? How many did this out of how many you have reloaded?

[gunwhatgun]

I was setting up a new Lee Loadmaster a couple of days ago and had this exact same thing happen, it happened at the seating/crimping die. I don't run a factory crimp die in the last position. The piece of brass it happened on was the same piece I had used to test all the other dies several time, meaning it hat been through the full length sizing die several times, so I chalked t up to fatigue in the brass. I pitched it is the cull bin, changed nothing and it hasn't happened again.

[WadeMod]

Okay, You need to retool slightly. Make seating and crimping a 2 step process. Step 1: Set your die 1/8inch too high and adjust seater below the crimp. Seat your set of bullets to the cantilever. Step 2: Raise up the seater and with your first shell inserted slowly lower the die till the crimp is barely making contact. Retract the shell and lower the die 1/8 turn for test crimp. Readjust accordingly. I acknowledge you are using a 3 die set and this would apply to a 2 die set. Look for an obstruction in either die.

Edited November 29, 2019 by WadeMod
grammar

[gregintenn]

Case length good?

Just for chits & giggles, measure the diameter of that bullet.