A tank's gun, which can be a cannon, autoloader, or howitzer, is the tank's main weapon.To decide which gun to mount, you must look at the penetration, average damage, and rate of fire as very important considerations for choosing a gun.
Not all guns that are available for a tank can be mounted on any turret. If there is a turret module preceding a gun on a tank tech tree, you will need to research and install it before mounting the gun.
A destroyed gun will lock, preventing the tank from firing until it is repaired, and a damaged gun will fire with drastically reduced accuracy.
Damage - The amount of hit points the shell takes from the enemy tank with a hit. Measured in HP (Hit Points), The gun damage statistics are usually written in a format such as #/#/#: referring to the shell types available for the gun, usually AP/APCR/HE ammo types.
Penetration - The penetration of the weapon refers to the amount of flat metal armor the gun can penetrate in millimeters (mm). Penetration is calculated as if firing at flat armor at a range of 100m, and is usually written in the #/#/# format. Again, this refers to the different shell types available for the gun.
Shells - The available shell types for the guns are determined by the color of the damage and penetration attributes: AP, APCR, HE, HEAT. For more info, see Ammo.
Rate of Fire - The rate of fire of a gun is the number of shells that can be fired in a particular span of time, also known as RoF. The rate of fire of a gun is measured in rounds per minute, and for conventional guns is another way to to state the reload time. For guns equipped with a magazine, the given rate of fire is the sustained rate of fire, or the average firing rate including the magazine reload time, not the burst firing rate of a single magazine.
Accuracy - The accuracy of the gun is the maximum shell dispersion when the sights are fully closed/contracted. The accuracy of a gun is measured in meters, indicating the amount of dispersion when fired at a target at a distance of 100m. The shell dispersion is also affected by Gaussian distribution.
Aim Time - The time it takes in seconds for a gun to come to full aim.