I just had 5 FTF issues on my shadow 2 during 500 round practice and determined culprit to be this brass.
Gun stopped out of battery and I had to tap round out of gun from bore.
Only CBC brass loaded longer than any of my other range pickup brass. The other brass was consistently 1.090 but cbc came in 1.100+. I went through a couple hundred rounds in my bag and sure enough, all the CBC was 1.100+. Found 26 so I feel confident that it wasn’t random.
It was causing bullet to hit rifling, which is a pain to get it out gun. Glad it was practice, as this jam pretty guarantees a zero if it happens on a stage.