if your question is: how many rounds will a barrel last? it depends whether the barrel is CHROME LINED or not. when i say chrome lined i'm not talking about a barrel made with chrome and moly but i'm talking about mil spec barrel with a CHROME LINED BORE&CHAMBER. If your barrel is a CHROME LINED one, i read somewhere (can't recall where) that i'd last 20.000, that's inside of mil specs (and of course) we are talkin about a well taken care barrel, with no lack or over cleaning.
Keep your barrel clean, lubed (ONLY WHILE IT IS IN THE SAFE) and you'll have fun for a long long time b4 you have to get a new one.
I hope this helps
HUNTER FROM ARGENTINA
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oh two more things...your barrel will be chrome lined whether it is marked on it or not, if it is a govt contract barrel i.e. bushmaster, colt armalite etc, and if it's not (chromed) it'd last half of the life of a chromed one.
AGAIN
HUNTER FROM ARGENTINA
OUT.