Yes, as are most AR-15 variants and clones from Eugene Stoner's original design. Gases are vented from the gas block located under the front sight post on the barrel through the gas tube back into the receiver of the rifle, where it meets the gas key that is attached to the bolt carrier. The expanding gases then thrust the separation of the gas key and gas tube, thus cycling the bolt, both ejecting the spent cartridge on rearward travel and loading a new cartridge on forward travel. This is known as auto-loading. Many newer designs are now using Gas-piston operation rather than Gas-tube, as this enables better cycling of action and far less fouling of the receiver from the vented gases inside the action itself.
Gas operated, magazine fed, select fire, 5.56 carbine.
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 impingement gas-operated, magazine-fed carbine. It has a 14.5 in barrel and is 33 inches long.. It weighs 6.5 lbs.
The M4 CARBINE IS BETTER THAN THE M16.
No one will give you an M4 rifle/carbine for free.
M4 is the carbine- shorter barrel
The Colt M4 Carbine .22 is a replica of the real M4 but in .22 caliber.
There is an M4 carbine in Call of Duty: Modern Warfare 2.
The M4 carbine has a muzzle velocity of 2,970fps(884m/s).
5.56mm
The gas propelling the bullet is tapped, and operates the bolt mechanism.
While the M4 Carbine is intended to fire a 5.56x45mm NATO round that is distinct from the .223 Remington, both are centerfire cartridges. So yes, the M4 Carbine is a centerfire rifle.
Perhaps they just forgot to add the "A1" to the nomenclature in CoD4. But yes, you are correct - the standard M4 carbine has the three round burst feature, while the M4A1 and the Canadian variant of the M4 (the C8) have full auto capability.