Find out some cool facts about the firearm that has recently seen extensive use in Iraq and Afghanistan.
The M4 carbine is a shorter and lighter variant of the M16A2 assault rifle. The M4 is a 5.56×45mm NATO, air-cooled, direct impingementgas-operated, magazine-fed carbine. It has a 14.5 in (370 mm) barrel and a telescoping stock.
The M4 carbine is heavily used by the United States Armed Forces and is replacing the M16 rifle in most United States Army and United States Marine Corps combat units as the primary infantry weapon.
The M4 is also capable of mounting the M203 grenade launcher. The distinctive step in their barrel is for mounting the M203 with the standard hardware.
The M4 is capable of firing in semi-automatic and three-round burst (like the M16A2 and M16A4), while the M4A1 is capable of firing in semi-auto and full automatic (like the M16A1 and M16A3).