The M16A4 is the fourth generation of the M16 series. It is equipped with a removable carrying handle and a full length quad Picatinny rail for mounting optics and other ancillary devices. It was the standard issue assault rifle of the United States Marine Corps at the time of the apocalypse. The M16A4 trigger group uses safe/semi/burst selective fire, but does not have a fully-automatic option.
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