Never Hear'ed
As stated, mine does not have a ton of rounds thru it. And the rounds that have been fired thru it were my my med pressure loaded handloads.(52gr @ 2850fps)
I have never seen any reports of the longivity of this gun. Me....?.....,If I were planning to put 5,000+ rounds thru a AR it would not be ANY carbon(upper and/or lower)firearm.
Allow me to say also,If you ever find one(NIB) for $650....SNAP IT UP.
Good Shootin' --- pruhdlr