The M4 and its variants fire 5.56x45mm NATO ammunition (or .223 Remington ammunition) and are gas-operated, air-cooled, magazine-fed, selective fire firearms with a multi-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 with curvature at the end. The M4 is similar to much earlier compact M16 versions, such as the 1960s-era XM177 family. Some of those visual designs are obvious in both weapons, however most of the similarities are not very noticeable.
As with many carbines, the M4 is handy and more convenient to carry than a full-length rifle. The price is slightly inferior ballistic performance compared to the full-size M16, with its nearly 6" (15 cm) longer barrel. This becomes most apparent at ranges of 300 yards and beyond. Statistically, however, most small-arms engagements occur within 100 yards. This means that the M4 is very much an adequate weapon for the majority of troops. The marginal sacrifice in terminal ballistics and range, in exchange for greatly improved handling characteristics, is usually thought to be a worthwhile compromise.
While the M4's maneuverability makes it a candidate for non-infantry troops (vehicle crews, clerks and staff officers), it also makes it ideal for close quarters battle (CQB). The M4 was developed and produced for the United States government by Colt Firearms, which had an exclusive contract to produce the M4 family of weapons through 2009; however, a number of other manufacturers offer M4-like firearms. The M4A1, along with the M16A4, have mostly replaced the M16A2; the U.S. Air Force, for example, plans to transition completely to the M4. The M4 is also the standard rifle for U.S. Air Force Security Forces members whether at home station or deployed abroad. They maintain a yearly qualification on it.
The United States Marine Corps has ordered its officers (up to the rank of lieutenant colonel) and Staff Non-commissioned officers to carry the M4A1 carbine instead of the M9 handgun. This is in keeping with the Marine Corps motto, "Every Marine is a rifleman." United States Navy corpsmen will also be issued M4A1s instead of the M9.
Replica had bean made of metal and abs. Body, outer barrel, hop up unit, magazine, stock pipe and gas pipe are made of metal while stock, grip and front grip are made of ABS. Battery is placed in the front grip.
Replica has adjustable hop up system, wich is responsible for greather range and accuracy. It may be accessed with use of reload lever wich will open dust cover there is the adjustment placed.
- Battery charger