If I had to choose a barrel profile, it would be the MSTN/Noveske profile for that Intermediate gassed 16".
After that, the older pencil FSB contoured DD units are up there for a fixed sight barrel - but yeah, anybody who pays extra for M4 profile is probably ignorant of the reasoning behind any of this - that was once me.
عندما تصبح الأسلحة محظورة, قد يملكون حظرون عندهم فقط
کله چی سلاح منع شوی دی، یوازي غلوونکۍ یی به درلود
Semper Fi
"Being able to do the basics, on demand, takes practice. " - Sinister
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