I have a used Bushmaster Carbon 15 for sale. It's chambered in 5.56 (shoots .223 also) with 1/9 twist pencil barrel. This rifle is lightweight (5 lbs) and easy to carry. Barrel is 16" length. Show in picture with MagPul front grip. Also included is a UTG quad rail that extends past the gas block when installed. If interested I can install before purchase. Lowest I have find this one for sale new is $650. I'm asking $500 cash. FFL not required but I prefer to do so. Will take care of the fee for transfer.