Gun



The main weapons in Left 4 Dead are divided into two tiers. The first is available to every Survivor when the scenario starts. Weapons in the second tier can be found throughout the maps and at the end of the scenario, just before the finale. All weapons can be used to melee Infected within close combat, pushing them back.

There is currently no way to distribute weapons or ammunition among teammates. All weapons have an attached flashlight with an unlimited battery; however, the flashlight's beam is only visible to the player using that particular flashlight if the other player's game settings are set too low.

Picking up either tier of weapon from a table or other location holding new weapons (not from a dead Survivor) provides a full ammo refill, equivalent to interaction with an ammo pile.

Note: 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
These weapons have been seen in the Left 4 Dead 2 footage, according to Valve there will be lower versions of Tier 2 weapons such as a Tier 1 Hunting rifle.

The L4D1 weapons will make an appearance in L4D2, based on their appearances in L4D media.

Unknown Tier

 * Grenade Launcher
 * AK-47

Weapon Upgrades
In this video, flashes of a laser sight can be seen coming out of Rochelle's submachine gun before and after getting attacked by The Jockey.

http://www.youtube.com/watch?v=0y8aMpHhrLs - this video features a laser sight gameplay, so now we know that it increaces your weapon's accuracy upon picked up.

Sidearm
Each of the Survivors starts with a pistol.
 * Pistol
 * Dual Pistols (Acquired when a second pistol is picked up.)
 * Magnum (cannot duel wield)

Grenades
Each of the Survivors can carry either one Molotov cocktail or one pipe bomb.
 * Molotov cocktail
 * Pipe bomb

Close Combat Weapons
Close combat weapons are introduced in Left 4 Dead 2. The weapons are found at random points in the game (Any weapon can be obtained by any Survivor when found), you cannot use your pistols until you drop the close combat weapon. According to Valve, these weapons do little to no damage to some Special Infected. The only one mentioned was the Witch. However, it is widely assumed that this applies to the Tank as well. These weapons can kill Common Infected in one hit, and can even kill multiple Infected in a single swing. According GI the Witch can be killed with a single shot from the axe if placed in the back of her head. As seen in Dark Carnival footage at PAX, when picked up, the close combat weapon takes the place of a pistol. This means you must choose between infinite ammo in ranged pistols that do not kill as fast as a melee weapon, and a melee weapon that is not ranged but is instant kill. Melee weapons have a main function, which is the attack, and also a secondary push similar to the one that can be used with guns. Similar to using melee with guns, it can be used to push back Infected.
 * Axe
 * Baseball Bat
 * Chainsaw
 * Cricket Bat
 * Crowbar
 * Electric Guitar
 * Frying Pan
 * Katana
 * Machete
 * Tonfa

Usable Items
These items found in various places in campaigns and be carried, once carried the character cannot use any other weapons until thrown or dropped, you can also use this weapon to push back infected.
 * Gas can
 * Oxygen tank
 * Propane tank

Other

 * Minigun

Reload
. Reloading (default "R" on computer 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 anyway.

Pistols have a similar reload time to the submachine gun, but a much smaller magazine capacity. Dual pistols make reloading take slightly longer. 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 whilst reloading. Listen closely when a teammate yells, "Reloading" and offer cover fire, especially if they are using shotguns.

Glitches

 * If you start to reload and then pause your game the reload will still continue, though when you unpause the game you will have to reload again. This works best on an auto shotgun. If you use all the bullets, reload pause the game at the 8th bullet. It will reload the other two. Unpause the game and it will reload all 10 bullets again, It will still say 8 bullets until the 9th and 10th are entered into the gun.
 * Players can still reload while using their melee attack. This is highly useful during horde attacks.

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, but you still can be lucky enough to encouter this animation while using an assault rifle - it usually occurs when you've just used a pipe bomb or a Molotov. It appears that these animations were removed in the last few months, 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), all tier 2 weaponry spawns in groups; allowing players to choose which weapon they want to wield against the Infected.
 * In Left 4 Dead 2 beta footage, single weapons of different tiers can be seen, suggesting that players can choose if they wish to carry a different gun or continue using the same one. It also figures out that the weapon piles of 2 Tier 2 weapons make their appearance there.
 * 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 clip, reload the entire clip, melee or switch weapons.