Shop › FN BBL M16 BB 16" MID LENGTH 556 FN BBL M16 BB 16" MID LENGTH 556 $279.00 FN America Barrel, 16", 556NATO, 1:7 Twist, Button Broached, Mid-Length Gas System, M16 Contour, Fits AR-15, Matte Finish, Black 20-100041 Quantity: Add To Cart Added! FN America Barrel, 16", 556NATO, 1:7 Twist, Button Broached, Mid-Length Gas System, M16 Contour, Fits AR-15, Matte Finish, Black 20-100041