Sizing factory 300BLK and resizing 5.56 to 300BLK, both cases are having gouges cut into the case about halfway down and depending how fast/hard I run the case it cuts deep all the way down the side and leaves a small flake of brass.
I'm using the pad/roll lube method to add lots of lube, and forster bench rest die set.
At first I thought not enough lube, then I thought it may be a dirty die, or possibly a effective die with some kind of abnormality on the inside?