Good info thanks for posting. 10K rounds as fast as possible and the barrel is hot enough to cook off a chambered round and too hot to handle, that's a true torture test. I think i'll be alright with what steel I shoot, i'm not abusing my AR no where near as much as they did those.
That's a whole lot of bullets. Last time I heard about that kind of thing was an uncle who was firing a .30 aircooled at the Chosin Reservoir. He said he went thru 4 barrels in a couple hours. Got shot himself.