I just bought a brand new LMT lower/upper and when i looked at the barrel crown (inside the flash suppressor) i see something that looks like rust to me. It mainly covers a part of the rifling. I don't think it is copper fouling.
What do you guys think?
I is located a 2 o'clock. The pics could be better but it is the better i could do.
BTW the upper is brand new and never been fire (only test fired at LMT)
What do you guys think?
I is located a 2 o'clock. The pics could be better but it is the better i could do.
BTW the upper is brand new and never been fire (only test fired at LMT)

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