White Paper on M4.3-R4 COURTESY :- vrindawan.in Wikipedia The M4 carbine (officially Carbine, Caliber 5.56 mm, M4) is a 5.56×45mm NATO, gas-operated, magazine-fed, carbine developed in the United States during the 1980s. It is a shortened version of the M16A2 assault rifle. The M4 is extensively used by the United States Read More …