I apologize for the quality of the photos. I am limited by my abilities and equipment. I do not pretend nor want to be a photographer nor am I equipped as such.
Though not new to reloading/handloading, my experience with insipient case head separations and the signs has been limited. I had a military LC79 match brass case head separate once in a bolt action after 6 or seven firings. I had missed the signature "bright band" on that particular case. The band was much wider than what is shown in these pictures.
Am I correct in that these cases appear to be indicating insipient case head separation?
The two cases on the right actually have a pronounced, narrow ring that appears to be a crack. These cases have only been fired two times. The second firing was after neck sizing.
The load: Winchester case, WLR primer, 45.0g IMR 4064, Hornady 168g A-Max, C.O.A.L. = 2.800", Trimmed after first firing to 2.005".
My Hornady manual has no data for IMR4064, but my Speer manual indicates 45.0g to be a max. load. I worked this load up from staring loads over the last few months and it shoots 1.1" groups at 200 yards in my gun, so I have come to like this load very much.
These cases are from a new bag of brass. Is it possible this lot of brass is thinner, stiffer or otherwise different than the previous bag? They are different lot numbers (I checked).
Your comments are appreciated very much!