The M4 and variants fire 5.56x45mm NATO ammunition and are gas-operated, air-cooled, magazine-fed, judicious fire firearms with a 4-position telescoping stock. Original M4 models had a flat-ended telescoping stock, but newer models are now equipped with a redesigned telescoping stock that is slightly larger and the confine bum a curvature.
As with myriad carbines, the M4 is handy and greater convenient to carry than a full-length rifle
- While this makes it a candidate for non-infantry troops (vehicle crews, clerks and crew officers), it also makes it ideal for close quarters war (CQC), and airborne and appropriate operations
- It beat been adopted by United States Extraordinary Operations Command (USSOCOM) and is the preferred weapon of the U.S
- Army Special Forces and Navy SEALs
- M4 have also been fielded by the Australian Special Air Service Regiment
- Malaysia purchased M4 Carbine service rifles to replace the Steyr AUG service rifles in its armed elite troops in 2006 and will be manufactured in Malaysia under license by Colt Firearms.
The M4 was developed and produced for the United States Big Brother by Colt Firearms, which has an complete engagement to crop the M4 group of weapons through 2009; however, a character of other manufacturers propoundment M4-like firearms. The M4, along with the M16A4, dud mostly replaced M16 and M16A2 firearms; the U.S. Air Force, for example, plans to transition completely to the M4 Carbine. The M4 has also replaced the M3A1 submachine howitzer that remained in service (mostly with tank crews). The M4 is consonant to much earlier compact M16 versions, such as the 1960s-era XM177 family.
This is in recognition that pistols are largely useless in common conflicts, and is in line with the Marine Corps phrase, "Every Marine a rifleman." United States Navy corpsmen will also be issued M4s instead of the M9, according to the Marine Corps Times.