5.56x45mm NATO Barrels

Green Mountain 5.56 AR-15 Barrel 16" M4 Crowned Phosphate

Green Mountain 5.56 AR-15 Barrel 16" M4 Phosphate

Green Mountain 5.56 AR-15 Barrel 16" M4 Fluted Phosphate

Green Mountain 5.56 AR-15 Barrel 16" M4 Phosphate

Green Mountain 5.56 AR-15 Barrel 14.7" M4 A1 Phosphate

Green Mountain 5.56 AR-15 Barrel 14.5" M4 Phosphate

Green Mountain 5.56 AR-15 Barrel 10.5" M4 Phosphate

Green Mountain 5.56 AR-15 Barrel 10.3" M4 Phosphate

Stag Arms 18" 5.56 NATO SPR Fluted Stainless Steel Rifle Length AR-15 Barrel Premium Series 1:8 Twist

Aero Precision 5.56 Carbine M4 AR-15 Barrel - Pinned VG6 Epsilon SL - 14.5" (16" OAL)

4.5" 5.56 Nato Micro Pistol Medium 1:5 4150 Black Nitride AR-15 Barrel

10.3 Carbine 5.56 Government M-LOK Upper Assembly

8 Pistol 5.56 Government M-LOK Upper Assembly

10.3" 5.56 NATO 4150 CrMoV Carbine Government 1:7 Nitride Barrel

16 5.56 Phosphate Midlength M-LOK Lightweight Complete Upper

16" 5.56 NATO 1:9 Twist Phosphate Midlength Lightweight Barrel

16" 5.56 NATO 1:7 Twist Phosphate + Chrome-Lined Midlength Heavy Barrel

16" 5.56 NATO 1:9 Twist Phosphate + Chrome-Lined Midlength Heavy Barrel

16" 5.56 NATO 1:9 Twist Phosphate Midlength Heavy Barrel

16" 5.56 NATO 1:7 Twist Phosphate Carbine Heavy Barrel

16" 5.56 NATO 1:7 Twist Phosphate Midlength Lightweight Barrel

16" 5.56 NATO 1:9 Twist Phosphate Carbine Lightweight Barrel

16" 5.56 NATO 1:9 Twist Phosphate + Chrome-Lined Carbine M4 Barrel

16" 5.56 NATO 1:8 Twist Phosphate Carbine Government Barrel