M16 Assault Rifle

"An assault rifle; This shit's gettin' more like 'Nam every second."

- Bill

"Man, I wanted this rifle since I was nine."

- Ellis

The M16A2, also called Assault Rifle in L4D or M16 Assault Rifle in L4D2, is a Tier 2 replacement for the Submachine Gun and Silenced Submachine Gun offering a significant enhancement to the player's ability to hit targets and inflict damage; quite simply, it is a better overall weapon. It features a 50-round magazine with 360 rounds in reserve.

In summary, the Assault Rifle is unquestionably one of a player's best choices as a general-use firearm on account of its balanced accuracy, damage potential and adaptability.

Tactics
In Left 4 Dead, the Assault Rifle is the most flexible and capable weapon available. Whether it is clearing a room, mopping up, engaging a Horde or sniping a distant Special Infected, the Assault Rifle will carry it off. It does have some shortcomings, but these are relatively minor and do not affect gameplay very much.

However, in Left 4 Dead 2, the standard Assault Rifle faces strong direct competition from alternative weapons (e.g. the AK-47) and players need to make their choices with a finer understanding of each weapon's pros and cons.

The Assault Rifle has five main advantages: On the downside, the Assault Rifle has two potential shortcomings, both of which can be minimized by skillful players: Tactically, since the Assault Rifle normally only needs two or three shots to do its job and the recoil generated by full-auto firing degrades accuracy at mid to long ranges, burst firing or "headhunting" is highly recommended. The secret of firing short bursts (or even single shots) is to apply only a very quick and light pressure on the fire control button. If the player has trouble conserving ammunition, try to use a secondary weapon against Common infected, and use Assault Rifle against Special Infected, Hordes and the Tank.
 * Its projectile is capable of penetrating multiple targets (although not to the same degree as the Hunting Rifle or Sniper Rifle.
 * It has a high rate of fire which, together with its longer range relative to the shotgun family, make it a very potent weapon against Tanks.
 * It has the ability to fire on full auto (by holding down the fire control button) and to let off fast double-taps and short bursts (by applying light pressure to the fire controller).
 * It has a large magazine backed up by a generous reserve ammo allowance.
 * It has a tight cone of fire (limited shot dispersion) meaning that it is safer to use than a shotgun when firing near other Survivors.
 * It is easy to waste ammo if a careless player adopts the bad habit of firing on full auto at all times. In co-op play this can be risky since a full-auto team member can become a liability, due to that person's repeated self-inflicted ammo shortages.
 * On higher difficulties, the Assault Rifle's killing power is diluted relative to other weapons so that it requires at least three hits to take down a Common Infected.

Burst firing involves firing a short two- to five-round burst at individual targets before shifting aim and repeating the treatment. This is excellent when shooting at medium and long ranges (e.g. sniping a Smoker's head just above a distant roof line) and is effective on most difficulty settings except for Expert (wherein targets are more resilient). With burst firing, a player knows that after firing five or six bursts the magazine is about half-empty and is getting due for reload, something that is hard to gauge firing on full-auto.

"Headhunting" with the Assault Rifle takes advantage of its accuracy and the fact that Common Infected all have the same physical height. Firing at the heads of a Horde decimates their ranks quickly. (A variation, "Leg Chopping" works in much the same way: a crouching player aims low for their legs.)

With a team of four player-controlled Survivors in a finale, it is a good idea to have two players with Auto Shotguns and Assault Rifles respectively. Position the team in a closet or facing a choke point. The two shotgunners crouch in front while the two with Assault Rifles stand behind them and fire over their heads. When the Tank arrives, the team breaks up to engage and reform once it is dispatched. (Note that this tactic is less effective in Left 4 Dead 2, as the Director may spawn a Spitter (or a Charger in choke points like a hallway) to prevent Survivors from staying in one place for too long.)

Pros

 * Excellent accuracy and rate of fire allows survivors to mow down hordes if their aim is kept at head-height.
 * Can be used to resolve almost any type of threat with changes in tactics.
 * Laser sight effectively cancels out any accuracy problems.
 * A skilled user can conserve ammunition by firing in bursts or single shots.
 * Fast reload.
 * Fairly common to find; replenishing ammunition is easier as a result.

Cons

 * Has the lowest damage per shot of all the assault rifles.
 * Somewhat inaccurate without a laser sight when moving.
 * Burns through ammo faster than its counterparts during sustained fire.
 * The versatility of this weapon is a double-edged sword. It's good in most situations, but doesn't shine in any one situation. This is exacerbated by the fact that heavy deployment will result in chronic ammo shortages.
 * May be hard to fire single-shots.

Left 4 Dead 2
The Assault Rifle returns in Left 4 Dead 2, but has some new animations along with a new name: the "M-16 Assault Rifle". Compared with the other two rifles (the AK-47 and the Combat Rifle), it is the "middle of the road" assault rifle variant in terms of capacity along with balancing stopping power and damage with accuracy and range, making it good for almost any situation.

Behind the Scenes
Early screenshots show that the Assault Rifle lacked text on its left side at one time.

When the Assault Rifle was drawn in early versions of the game, the character would pull the charging handle as soon as they took the gun out. The sound for this animation is still played when the Assault Rifle is drawn out in the final version of the game.

The Assault Rifle was based on Counter-Strike ' s M4A1 assault rifle. Its "price" in the gun's weapon file is the same as the M4A1's, and it references the M4A1 in its "animation" listing. Its firing sounds are slightly modified versions of the sounds used for the M4A1. This is because in real life, the M4A1 is essentially a shorter M16.

It had a different reload animation as well. After replacing the magazine, the player would both pull the charging handle and hit the bolt catch.