Colt M16A2 20" machine gun barrel. Marked "C MP 5.56 NATO 1/7". Standard Government issue A2 barrel in 5.56x45mm NATO spec and 1/7 twist rate, GI contour for M203 or 37mm flare launchers. Like new condition, chromelined chamber and barrel, ground down bayonet lug, factory threaded muzzle. Comes with front sight, gas tube and barrel nut assemblies, everything you see in picture. $260 shipped to your door.
I can permanently fix a Cavarms A2 birdcage muzzlebreak for that military look for $20 more. It fits standard AR uppers, including Colt, Bushmaster, Armalite, DPMS, RRA, and Olympic arms. I accept Postal or Bank Money Order for payment.