Replica of a rare variant upper used on experimental carbines and Air Force contract riles as substitute for the "slick side" 604 type uppers. They are cut for a .250" front push pin, and are recessed (left side) for the 601 type front takedown pin.
Used AR-15 Pistol 5.56 NATO 10.5" Anderson Lower / RRA Upper - Used ...Click for more info. ... Angstadt Arms UDP-9 9mm AR9 Pistol 6" Barrel Glock Mag AAUDP09B06 ... The Gen II from Spike's Tactical is a heavy-duty upper receiver with several unique features that set it apart from other uppers on the market. It's made from a solid billet of 7075-T6 aluminum, employs a type III hardcoat anodized finish and weighs 10.25 oz. Spike's Tactical cuts the M4 ramps before the anodizing step, which increases reliability.