Tula/Wolf users may want to read this thoroughly, barrels "shot out" after 6k rounds... http://www.luckygunner.com/labs/brass-vs-steel-cased-ammo/
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.yeah.. cooking off rounds.. yikes.
I bet if they did the same volume but allowd cooling between, the wear would have been less.