AR Parts in 5.56x45mm NATO

HM Defense HM 5.56 Nato 9.5" Straight Fluted SS Barrel 9.5SS-P-STF-556-108

HM Defense HM 5.56 Nato 9.5" Straight Fluted CrMo Barrel 9.5CR-P-STF-556-108

HM Defense HM Twist SS bbl Rifle Upper Kit 16UP-TWSS-556

HM Defense HM Straight Fluted bbl Rifle Upper Kit 16UP-STFCR-556

HM Defense HM Spiral Fluted SS bbl Rifle Upper Kit 16UP-SPFSS-556

HM Defense HM Spiral Fluted bbl Rifle Upper Kit 16UP-SPFCR-556

HM Defense HM 5.56 Nato 16" Twist SS Barrel 16SS-C-TW-556-108

HM Defense HM 5.56 Nato 16" Spiral Fluted SS Barrel 16SS-C-SPF-556-108

HM Defense HM 5.56 Nato 16" Straight Fluted CrMo Barrel 16CR-C-STF-556-108

HM Defense HM 5.56 Nato 16" Spiral Fluted CrMo Barrel 16CR-C-SPF-556-108

Harrington & Richardson Retro M16A1 Stripped Barrel Assembly

Blem Harrington & Richardson Retro M16A1 20" AR-15 Upper 5.56 1:7 Rifle Length, Gray

Harrington & Richardson Retro M16A1 20" AR-15 Upper 5.56 1:7 Rifle Length, Gray

Blem Harrington & Richardson Retro M16A1 20" AR-15 Upper 5.56 1:12 Rifle Length, Gray

Harrington & Richardson Retro M16A1 20" AR-15 Upper 5.56 1:12 Rifle Length, Gray.

Harrington & Richardson Retro 653 16" 5.56 Carbine-Length AR-15 Upper w/ 1:7 Twist

Blem Harrington & Richardson Retro 723 16" AR-15 Upper 5.56 1:7 Carbine Length

BLEM Harrington & Richardson Retro M16A1 Upper Receiver, Black

Guntec USA AR 5.56 Cal Extended Takedown Pin Set Gen 2 Anodized Red

Guntec USA AR 5.56 Cal Extended Takedown Pin Set Gen 2 Anodized Purple

Guntec USA AR 5.56 Cal Extended Takedown Pin Set Gen 2 Anodized Green

Guntec USA AR 5.56 Cal Extended Takedown Pin Set Gen 2 Anodized Gold

Guntec USA AR 5.56 Cal Extended Takedown Pin Set Gen 2 Flat Dark Earth

Guntec USA AR 5.56 Cal Extended Takedown Pin Set Gen 2 Anodized Blue