Gun

"Long as we still got guns, we gonna' fight."

- Coach

"Guys! Big, badass, nasty weapons over here!!!"

- Zoey

The main weapons in Left 4 Dead are divided into two tiers. The first is the kindavailable to any Survivor when the scenario starts. Second-tier weapons can only be found later on throughout the maps such as at the end of the campaign just before or at the finale, as they are considered upgrades from Tier-1-weapons. Melee (shove-back, default "right-click (mouse2)") can be used while holding any weapon, on Infected (excluding the Tank, the Charger, and the Witch (except in some situations)) within close combat, pushing them back and delaying a threat.

There is currently no way to distribute weapons or ammunition among teammates without picking up another weapon to replace the slot of the weapon you wish to give. All weapons have an attached flashlight with an unlimited battery; however, the light emitted from the flashlight is only visible to player wielding it.

Picking up a weapon from a table or other location holding new weapons (not from a dead Survivor) provides a full ammo refill (as well as the magazine) of that weapon, equivalent to interaction with an ammo pile. This is useful for unloading an entire magazine, then picking up a new one so as to avoid having to reload the weapon.

Weapons will continue reloading despite the lack of reloading animation during melee attacks, provided that reloading starts before the melee attacks. This is extremely useful if out of ammo, or both primary and pistol need to be reloaded as it allows the player to shove back attacking Infected while their weapon reloads in the background. When it is fully reloaded (after 2-3 melees' time) it can be used to kill the staggering Infected.

Tier 1
Each of the Survivors has the choice of starting with one of either of the first tier weapons, but they can switch or restock ammo on checkpoints.

Tier 2
Each of the Survivors have the choice of switching their first tier weapons to one of these on later checkpoints. Picking a Tier 2 weapon up will automatically fill the reserve ammo.

Left 4 Dead 2
The following weapons can be found in Left 4 Dead 2. The original Left 4 Dead weapons will also make an appearance in Left 4 Dead 2, although some of them appear to be slightly tweaked have a new reload animation.

Sidearms
Each of the Survivors starts with a pistol.
 * Pistol (Can be dual-wielded, Left 4 Dead only)
 * P220 Pistol (Can be dual-wielded by picking up a Glock, Left 4 Dead 2 only)
 * Magnum (Cannot be dual-wielded, Left 4 Dead 2 only)

Grenades
Each of the Survivors can carry either one molotov cocktail, one pipe bomb, or one bile bomb.
 * Molotov cocktail
 * Pipe bomb
 * Bile bomb (Left 4 Dead 2 only)

Melee Weapons
Melee weapons, are a new class of weapon introduced in Left 4 Dead 2. They're found in some safe rooms and along the chapters of each campaign. Melee weapons do not have their own inventory slot, instead ,they replace the pistol if they are picked up. However, when incapacitated, a Survivor will draw a pistol to defend themselves until they're helped back up. They can kill Common Infected in range with one swing, and are capable of killing several in one swing. They can also instantly kill most Special Infected and deal heavy damage to the others, although due to the abilities of the special Infected, it's usually best to just shoot them. All melee weapons can be used indefinitely save for the Chainsaw, which runs out of gas eventually and the Survivor will then drop it. Melee weapons also have different rates of swings and will accumulate blood as they are used against the Infected.
 * Axe
 * Baseball Bat
 * Chainsaw
 * Cricket Bat
 * Crowbar
 * Electric Guitar
 * Frying Pan
 * Katana
 * Machete
 * Nightstick

Usable Items
These items are found throughout campaigns, and when picked up, you can't use any weapon until you throw them or drop them. You can shove with them, however. When shot, burned, or otherwise detonated, these items blow up or spread flames, making good tools for defending areas during Crescendos or Finales.
 * Gas can
 * Oxygen tank
 * Propane tank
 * Fireworks (Left 4 Dead 2 only)

Special Items
These items are special and are found at specific locations in specific maps. These weapons have no damage capabilities what so ever but will usually open a path or grant an achievement.
 * Gnome Chompski
 * Cola

Fixed Weapons
Over the course of the campaigns, the Survivors find fixed gun emplacements left behind by the military in their failed attempt to contain the Infection. They appear at certain finales and crescendo events and have an infinite supply of ammo. However they are prone to overheating, which renders them temporarily unusable. When a Survivor uses a mounted gun, they cannot move and can only fire in a fixed arc.
 * Minigun (Left 4 Dead)
 * Heavy Machine Gun (Left 4 Dead 2)

Reload
Reloading (default "R" on PC and "B" on the Xbox360) is the in-game action of moving ammo from your reserve ammo count to your usable loaded ammo. When you reload, your character will usually yell, "Reloading!" or something similar.

The pump shotgun and auto shotgun have the slowest reload time from an empty magazine, as each individual shell must be reloaded, so make reloading the shotgun after shooting a habit.

The submachine gun and assault rifle have the fastest reload times, which complements their high magazine capacities to make reloading nearly trivial.

The hunting rifle takes longer to reload than the other two magazine-fed weapons, but the person using it should have the least close quarters contact of all other Survivors anyway.

Pistols have a similar reload time to the submachine gun, but have a much smaller magazine capacity. Dual pistols make reloading take slightly longer, and incapacitated players take twice as long as normal to reload their pistols.

It is best to always reload before a finale or when a Tank is drawing near. While reloading in the heat of battle, it is best to run away when you are almost out of ammo and use your melee attack while reloading. Listen closely when a teammate yells "Reloading," and offer cover fire, especially if they are using shotguns.

If you melee while you are reloading, this will not interrupt your action. You will continue to reload until you are finished or attacked by a Special Infected such as the Hunter, Tank, Smoker, Charger, or Jockey. This is extremely helpful against horde attacks, as it allows you to push them away from you to finish reloading you weapon.

Glitches

 * If you start to reload and then pause your game, the reload will still continue. However, when you unpause the game you will have to reload again. This works best on an auto shotgun. If you use all of the bullets, pause and then reload the game at the eighth bullet. It will reload the other two. Unpausing the game will cause it to reload all 10 bullets. However, it will still say eight bullets until the ninth and 10th are entered into the gun. This glitch is only effective on the PC version.

Cooldown
Cooldown is the minimum length of time in the Left 4 Dead series that a Survivor or an Infected needs to wait after using an ability before they can use it again.

The Survivors
Main article: Melee

In Left 4 Dead the Survivors have no special abilities and therefore do not need to wait to use their abilities other than healing, shooting and reloading. However, in all gameplay modes of Left 4 Dead 2 and Versus mode of Left 4 Dead there is an exception called Melee Fatigue. After couple of melee uses, the Survivors will need to wait 2 seconds until they can use it again, and if they will keep using it, they will have to keep waiting 2 seconds each melee attack until fully rested for couple of seconds.

Originally this was not in the game until Valve received complaints of people not actually "Firing their gun" in Versus and Campaign matches. When the Left 4 Dead DLC known as the Survival pack came out, Valve added in this new system.

The Infected
The Infected have different abilities, and therefore different cooldown times.


 * The Boomer has to wait 30 seconds before being able to vomit on the Survivors again.
 * The Hunter does not have a cooldown on Pouncing, but it must wait 2 seconds before being able to leap if it stood up.
 * The Smoker's tongue takes 15 seconds to rewind if it breaks or is removed from a Survivor. In Versus, it takes 5 seconds to rewind if it misses.
 * The Tank takes 3 seconds to swing his arm again after punching and to rip the ground to throw concrete. The Tank has no punch delay after a rock throw, meaning it can hit a Survivor twice.
 * The Hunter, Boomer and Smoker's secondary claw attack has a 1 second cooldown.

Behind the Scenes

 * In the game_sounds_weapons.txt file, listings for a flare gun and a LAW rocket launcher can be found. It is likely that these weapons were scrapped early in development, as none of the pre-release footage shows either of these weapons.


 * All of the weapons in Left 4 Dead are based on the programming used for Counter-Strike: Source's weapons. Most of the weapons are based on either weapons usable by both teams or Counter-Terrorist-exclusive weapons, with the only exception being the Dual Pistols, which is based on the Dualies, a Terrorist-exclusive weapon.


 * Weapons originally did not have flashlights on them, as seen in pre-release pictures. In addition, their world models had blood on them.


 * All weapons originally had two reload animations; when the magazine is empty and when the magazine is not. The animation that played when the magazine was empty is longer than the other animation because the player need to cock the gun in order to load a new round. Most of the "empty" animations were removed from the game, but can still be seen in the Left 4 Dead Authoring Tools. The only weapons that still use their empty reload animations are the pump and auto shotgun.


 * It appears that the animations relating to the other 3 weapons (Uzi, Assault Rifle, and Hunting Rifle) were removed shortly before release, as they can be last seen in gameplay footage dated September 2nd, 2008, but are gone by the time footage is released on October 15th, 2008.

Trivia

 * The posters before each level sometimes show characters with scoped MP5s, but they are not usable in the actual game.
 * In Left 4 Dead (with the exception of one area each in the 3rd and 4th chapters of Death Toll and in Crash Course), all tier 2 weaponry spawns in groups; allowing players to choose which weapon they want to wield against the Infected.
 * The flashlight is mounted on each gun and is sensitive to how the player moves it. It scatters with players' movements when they reload part of a magazine, reload the entire magazine, melee or switch weapons.
 * An interesting thing to note is that the pistol is the only weapon that actually has a reason to stay attached to you. Weapons put on your back don't have a strap keeping them on, and molotovs, pipe Bombs and pills also seem to float on the player's waist.
 * If you spawn a usable item while you're still holding one, the one you dropped will be ineffective, meaning it wont get set off no matter what. Picking it up and throwing it solves this.
 * It is odd that the "fatigue timer comes up when you melee with guns but fighting with a melee weapon, there comes no timer, even though in reality the use of melee weapons would exhaust you much quicker than hitting with the backside of a gun.
 * In Left 4 Dead 2, not all weapons have a full stock of ammunition. When you approach a weapon close enough, it will say if the weapon is fully loaded or not.
 * In Left 4 Dead 2, it should be noted that upon picking up a melee weapon, Survivors drop their pistol (if they are dual wielding, they will drop both pistols). However, when they are incapacitated, they still pull out a pistol, and once revived, the pistol is no longer part of their inventory and the melee weapon is still in the pistol slot. This is the game designer realizing that if a teammate is pinned a melee weapon would be useless.
 * Also in Left 4 Dead 2, all melee weapons have a blur effect when swung. This includes both the primary fire (swinging the weapon) and the secondary fire (pushing with the weapon).
 * When Picking up ammo from a stock pile in Left 4 Dead, it would only fill the reserve ammunition to its maximum capacity. In Left 4 Dead 2, picking up ammo from a stock pile would fill the reserve past its usual limit, to the point that if you were reload after, your weapon would be fully loaded. This was likely done because of when a player would pick up ammo for an empty gun, they would then have to reload and pick up more afterward to fully replenish their reserves.
 * In Left 4 Dead 2, typing "give melee" in console will give you a glitched melee weapon. When taken out it appears to be glitch arms flying all over the place. It has no HUD icon, either. If traded for a different melee weapon or a pistol, the world model will appear as a Hunter's arms.
 * In Left 4 Dead 2, typing "give hi_claw" in console (replacing "hi" with the name of a Special Infected) will cause an apparent glitch. The "Infected_claw"s are most likely supposed to be the weapons that Infected players use while playing a Versus game. However, when spawning is attempted, a P228 will drop on the floor that you cannot pick up.
 * Currently, the weapon smoke effect in Left 4 Dead 2 is bugged, as the smoke comes from behind the gun, rather from the muzzle.
 * When you finish a chapter holding a melee weapon, on the next chapter all of the blood on the weapon will be gone and clean.
 * When Picking up a firearm, it's interesting to note that the weapon does not leave the table/truck/ground etc. wherever you pick it up. Instead you receive a copy.