The Chrome Shotgun is a Pump Shotgun variant in Left 4 Dead 2. It has the tightest spread of all of the shotguns in the game, which makes it more effective against distant targets than the other shotguns. Its high damage per shot and high penetration against Common Infected also makes it a good weapon for handling Hordes. Compared to the Pump Shotgun, it has a tighter spread and more damage per pellet, but fewer pellets overall, leading to a negligibly lower amount of total damage (the difference between the total damage of all 64 shots done by this and the Pump Shotgun is only 128 damage; in other words, close to half a shot).
The Chrome Shotgun's accuracy makes it more effective than the Pump Shotgun at taking out Special Infected from a distance.
Due to the tight spread of the Chrome Shotgun, it's best to find a narrow passageway to kill multiple Common Infected with one shot.
The Chrome Shotgun's fairly tight spread makes it an effective weapon for cr0wning Witches.
Like with all shotguns, reload as frequently as possible and stock up on ammo whenever you can.
Dual Pistols are the most effective side arm for any shotgun, although the Magnum works well, too. Avoid using melee weapons, as the Chrome Shotgun benefits more from a ranged secondary weapon.
Explosive Ammunition makes your shotgun fire slugs with large explosions. You can use this to shoot the ground which will take out large numbers of Common Infected and knock back Special Infected.
Take advantage of Incendiary Ammunition with the Chrome Shotgun to ignite multiple Infected with one shot. The weapon's accuracy (for a shotgun) also means that you can get distance shots on Special Infected and still kill them through burn damage.
The Chrome Shotgun may be a good weapon of choice in Versus mode in the early rounds when it is required to kill certain Special Infected at medium ranges, especially when a Survivor only has one pistol. The Pump Shotgun may seem like the better choice, but veteran players will often attempt to attack from a distance which the aforementioned weapon cannot instantly kill Special Infected. This can lead to severe consequences.
While being attacked by Hordes, it is best to shove after each shot to push back Infected while chambering the next shell.
You can shove as you reload to maintain a full or nearly full clip while still stopping the infected from hitting you.
If your teammate is being attacked on the other side of a thin wall, you can use the Chrome Shotgun to shoot through the wall to save them.
While the Chrome Shotgun's accuracy is notably better compared to that of the Pump Shotgun, it is still inadvisable to use it on Infected that are near teammates. Switch to a secondary weapon to avoid friendly fire.
Be careful not to aim anywhere near gas cans or other carriable explosives that you don't want to ignite, especially in Left 4 Dead 2's The Atrium, The Port, and Scavenge mode. The Chrome Shotgun's spread can easily cause pellets to spray towards unintended targets so long as they are still in front of the shooter.
Not effective for long-range targets or against Hordes in big, open spaces.
The Chrome Shotgun must pump every time you fire, making it hard to hit fast-moving targets.
Friendly fire becomes a danger on Expert difficulty, as one shot can incapacitate a teammate at close range from full health.
It has a long reload time if you are reloading from empty or a nearly empty.
Smokers and Spitters will be very hard to hit at long distances, making them hard to kill safely.
The slow rate of fire and reload speed, as well as the damage penalty for all shotguns, means the Chrome Shotgun takes the longest of any primary weapon to kill the Tank, excepting the Steyr Scout and Accuracy International AWSM (though it ties with the Pump Shotgun).
The Chrome Shotgun is modeled after the Remington 870 Marine Magnum. Valve most likely renamed and recolored it as the "Chrome Shotgun" to avoid licensing issues and make it easier to identify.
In early gameplay videos, the Chrome Shotgun shared the Left 4 DeadPump Shotgun animations. The stats were shared as well.
The shotgun's animation, instead of pumping downwards due to recoil, resembles Team Fortress 2's shotgun pump animation, but slower.
Shoving immediately after firing may slightly increase the rate of fire by skipping the pump animation. This also works with the Pump Shotgun.
Within 100 game units, all shotguns deal 5x damage to Common Infected (which makes a difference on Expert Realism). These variables can be configured in the developer console.
All shotguns suffer from reduced damage against the Tank. This makes sense, since buckshot is notorious among hunters for being a very poor option when hunting big or thick skinned animals on account of the low ballistic coefficient of shot pellets. This is also a balancing fix because the Tank is much easier to hit with all of the pellets of the buckshot, compared to most other weapons where attacking an enemy with a large hitbox would not affect gameplay very much compared to a normal sized enemy.
This, along with other shotguns, is hard-coded. Its attack interval and reload/shell-insertion interval is impossible to be changed through the modification of the weapon scripts -- technically you can, but it won't do anything, as the entity will still shoot at its default attack interval, and reload at its default shell-insertion interval. Upon reloading with an increased capacity through modification, it suffers an animation glitch upon the 17th shell and beyond.