When an enemy ship gets within a specific range — displayed under the Artillery tab in the ship details in Port — the secondary battery guns that can engage will automatically turn to fire at that enemy ship. Because they are not player-controlled, secondary battery guns are highly inaccurate and misses are more prominent than hits.
- If there are multiple targets on one side of a ship, the nearest target will be automatically selected. Captains can hold CTRL and left click with their mouse to to focus an enemy target for their secondary battery; this will order the guns to focus that target regardless of range. Unlike anti-aircraft guns, selecting a focus target for the secondary battery provides no bonuses of any type. (The commander skill Manual Fire Control for Secondary Armament changes this mechanic. See below for more information.)
- If there are targets on both sides of a ship, the guns on each side will engage the nearest target. Only one target can be manually selected, regardless of which side of the ship they are on.
Like main battery guns, secondary battery guns can fire both high explosive or armor piercing rounds. The choice of which round is fired is not up to the player; instead, it is fixed
High Explosive (HE)
Most players prefer secondary guns that fire HE shells due to their ability to start fires. Their high rate of fire and number of shells means that fires can happen relatively often, especially against larger enemy capital ships. Any and all captain skills and flags that affect fire chance improve the fire chance of secondary guns as well.
On the other hand, some secondaries fire AP shells. This has a benefit and a side effect. On the plus side, the shells do more damage and can citadel some ships if they show broadside; on the other hand, AP shells cannot light fires, and have difficulty dealing with an angled target. The gun description will tell you if the shell is AP or not.
There are three ways to increase the effectiveness and accuracy of a ship's secondary guns: commander skills, signal flags, and upgrades.
There are five commander skills that affect secondary guns and improve their performance.
- Adrenaline Rush (2 skill points) starts speeding up the reload of secondary guns a ship progressively takes more and more damage.
- Basic Firing Training (3 skill points) increases the reload speed of all secondary guns by 10%.
- Demolition Expert (3 skill points) increases the fire chance of secondary battery shells by 2%.
- Advanced Firing Training (4 skill points) adds 20% to the range of secondary guns.
- Manual Fire Control for Secondary Armament (4 skill points) reduces the dispersion of secondary armament by -15% for ships of Tiers I-VI, and -60% for ships of Tiers VII-X. This dispersion bonus only applies to the manually focused target that the captain has selected by holding CTRL and left-clicking. Additionally, ships under the command of commanders with this skill will NOT fire their secondary guns at any target other than the one selected as a focus target, regardless of range.
Signal FlagsThere are three signal flags that improve secondary performance.
- Mike Yankee Soxisix () adds 5% to a ship's secondary battery range, and decreases the dispersion and reload time by -5%.
- Victor Lima () adds a +1% chance of causing a fire for shells with a caliber above 160mm, and a +0.5% chance of causing a fire for shells with a caliber below 160mm. Most secondary guns are 155mm and below, so the majority will see a .5% increase in fire chance.
- India X-Ray () also adds a +1% chance of causing a fire for shells with a caliber above 160mm, and a +0.5% chance of causing a fire for shells with a caliber below 160mm. However, this comes at a price, adding a +5% chance to the risk of the ship's magazine detonating.
There are four upgrades that affect the secondary battery.
- Auxiliary Armaments Modification 1 () (Slot 1) increases the survivability of secondary mounts by 100%.
- Aiming Systems Modification 1 () (Slot 3) adds 5% to the maximum range of the secondary battery and reduces the dispersion of secondary battery shells by 5%. Because they share an upgrade slot, this upgrade is mutually exclusive of Secondary Battery Modification 2.
- Secondary Battery Modification 2 () (Slot 3) adds 20% to the max range of the secondary battery and reduces the dispersion of secondary battery shells by 20%. Because they share an upgrade slot, this upgrade is mutually exclusive of Aiming Systems Modification 1.
- Secondary Battery Modification 3 () (Slot 6) decreases the reload time of the secondary battery by -20%.
All of these effects are cumulative. For example: combining Manual Fire Control for Secondary Armament with Secondary Battery Modification 2 on a Tier VIII ship that equips a Mike Yankee Soxisix signal will reduce the dispersion of secondary battery shells by 85%.