AR Barrel question

[hdchaplain]

I see a lot of used rifles for sale with approximate number of rounds down the pipe. Since I am a novice to the AR world do the barrels get shot out after a time and if so about how many rounds could one expect from a given barrel? Loaded question I know.

 

[shibumiseeker]

For a precision barrel, 3-5k for .223 before you see significant degradation in performance.

For a plinker or a combat weapon, tens of thousands of rounds.

There's lots of variables including how hot the rounds are and the material from which the barrel is made.