A broken bunter is something I thought of but it would have been a very clean break since you really have to look at the case head with a jeweler’s loupe to see the rough finish. Of course, they could have cleaned up the broken area and put the bunter back to work.
Is that something normally done?
If you read the reference Glenn posted, it’s obvious that Roy Weatherby was having all kinds of problems in getting cases and maybe something like that was done out of frustration just to get some usable brass.
You’re right. Maybe that is the answer.