Mac, if this brass is what you got from me PM or email me.
I am pretty sure it is.
This had ALL been fired in an FA. As to number of loads and type of loads, I honestly could not say. I bought the FA from an IHMSA mentor of mine. One of the most cautious and conservative shooters I know.
I really really doubt a high pressure load. Maybe loaded a lot.
A revolver guru local to me looked the FA over real hard after I bought it. I knew it had been shot a LOT and was just wanting to make sure everything was good before I started with it or if it needed to go back to FA for a rebuild. It was fine as expected other than a bit of wear from use.
I have experienced as mentioned above a "belt" of sorts showing up on brass over time from use. I have some 30-20 brass that has been loaded a bunch that exhibits the belt. Split it length wise with a dremel just to check it, looked like a donut on the out side, inside looked as virgin.
Not making excuses or dismissing anything. From me being here the short time, I am pretty sure we are all alike in not throwing things away. Thus my usage of high mileage cases.
Jeff