Ar-15 M4a1 5.56 16" Barrel Fn
Ar-15 M4a1 5.56 16 Barrel Fn.
This FN manufactured AR-15 barrel is produced to the same specifications as US military issue barrels. Starting from 4150 steel alloy, the barrel is button broached with a 1-7 right-hand twist per military specifications. This process ensures a consistent & uniform bore. Bore is then chrome lined & exterior finished with a mil-spec, black phosphate. Muzzle features ½-28 threads for attachment of a standard A2 flash hider, or the muzzle device of your choice. Barrel is chambered in 5.56x45mm NATO & includes a barrel extension with M4 feedramps. This particular barrel features the M4A1 profile and a carbine length gas system. OD at the gas journal is .750”.
Big Book Catalog, Issue:70, Page:019