The M4A1 is one of two automatic rifles unlocked by default, the other being the AK74.
The M4A1 is a balanced rifle, offering strong stats in every category. It is best suited for mid-range engagements but is perfectly capable even in close quarters. It is very similar statistically with the AK74, but offers a slightly higher fire rate and better control at the cost of one point of damage.
It is both suitable to beginners, and a viable option for experienced players, offering a competitive time to kill and a fire rate high enough to be forgiving, but low enough to allow for decent ammo conservation.
The M4A1 is a fully-automatic variant of the M4 carbine, which in turn is a shortened variant of the M16A2 assault rifle. Designed in the 1980s by American arms manufacturer Colt Firearms, the M4A1 was primarily made for use by special operational forces. However, the M4A1 has gone on to see more widespread adoption outside of its initial role, including replacing its parent M16 rifle as the standard-issue rifle for the United States Army.
Trivia
The M4A1 is one of only four guns in the game with fully modeled cartridges in the magazine. The cartridges are dynamic, accurately showing two, one, or no rounds during the magazine check, depending on the magazine's remaining capacity.
The other weapons that model cartridges in the magazine are the M249, the Unica, and Rsh12.
Unlike its real life counter-part, the M4A1 in-game offers a burst-fire mode, alongside the usual full-auto and semi-auto settings.
The M4A1 depicted in-game lacks the distinctive M16A2-style carry handle and gas-block mounted front sight.
Instead it features a flat topped upper receiver and gas block, with Picatinny rail and attached iron sights.