There are three types of player-loadable ammunition in World of Warships: high explosive (HE), armor piercing (AP), and semi-armor piercing (SAP).
Understanding how the shell types behave and when to use them is important to achieving optimum results in battle. This article focuses on which ammo to select in a given situation. For details of how the types interact with armored targets, please see the dedicated article Armor Penetration.
- 1 HE shells
- 2 SAP shells
- 3 AP shells
- 4 Selecting ammo type
- 5 Which type to use?
- 6 Guns and their shell types
- 7 Torpedoes
- 8 Airborne Ordnance
- 9 Notes
There are three main parts to a shell: a casing, an explosive charge, and a fuse to set off the charge. Varying these components changes how the shell performs when it smacks into something hard.
High Explosive (HE) shells have a relatively light casing, are packed with high explosive, and are fused to explode on contact. They are not expected to punch through heavy armor but to create a blast volume of concussion, flame, and fragments, perhaps penetrating structure or light armor and wrecking things like modules within the blast volume. They also start fires.
The performance of an HE shell is determined by two things: the caliber of the shell (and thus the amount of high explosive it contains), and certain national attributes (e.g. IJN HE will do more damage than other nations, and KM HE less.) In summary, HE shells:
- can penetrate light armor for direct ship damage;
- do not ricochet;
- do not overpenetrate;
- do produce Shatter ribbons, but these are No Penetration hits that may well do blast damage;
- explode on contact (with anything) creating a blast volume in which lightly armored modules can be damaged or destroyed, even if the shell does not hit the ship itself;
- can start fires;
- glow yellow in flight.
Direct damage to the ship is inflicted only if the shell penetrates the part of the ship it hits. Blast damage and fire may be inflicted whether or not it penetrates. Modules protected by 76mm or thicker armor are immune from blast damage so larger main gun turrets are safe, but most if not all secondary and AA batteries and torpedo launchers are vulnerable, as are engines and steering gear. A blast might even ignite a magazine.
HE shells can be used in different ways, depending on the target. For a very lightly armored target like a destroyer, AP can simply blow right through it without fusing, doing little damage, while HE will always explode and usually penetrate. For a very heavily armored or angled target, incapacitating modules can be important but setting fires is the main purpose of HE. While the penetration damage of a light cruiser's HE might be negligible, multiple and repeated fires are a real danger even to behemoths such as Yamato.
The IFHE skill
The commander skill Inertia Fuse for HE Shells increases HE penetration by 25% at the expense of a halved base fire chance (the additional fire chance of signals and skills is not halved). This skill typically enables cruisers to penetrate the plating of battleships of the same tier but at the cost of fire chance. It is best used on ships that can both penetrate common armor thresholds with the additional penetration and already have low base fire chance. IFHE is frequently paired with the Demolition Expert skill to recover some of the lost fire chance.
Example The Tier VIII cruiser Cleveland has a stock shell diameter (caliber) of 152 mm. The Caliber/5 rule yields a value of 30.4 mm. Without the skill an HE shell from Cleveland can penetrate 30 mm armor, from any angle.
Now the commander acquires the IFHE skill. 30 * 1.25 = 37.5, rounded down to 37. An HE shell from Cleveland now can penetrate 37 mm armor, from any angle. Her shells also lose half their base fire chance.
Semi-armor-piercing (SAP) shells combine the features of both AP and HE shells. The nose of the casing is thickened to form a penetrator cap, of a sort, with less high explosive than HE but more than AP shells can pack in. SAP is fused with a short delay, like AP.
Like HE shells, SAP armor penetration is not a function of shell velocity or angle of incidence. Penetration depends on the caliber of the shell and the nominal thickness of the armor. The shell penetrates and deals damage if the penetration value is higher than or equal to the thickness of the armor. The value for each caliber appears in the chart below.
- often have a higher maximum damage than the gun's AP;
- can ricochet but have very favorable ricochet angles — even better than those of American and British AP;
- can overmatch like AP shells;
- can penetrate thicker armor and cause greater damage than HE shells;
- cannot penetrate multi-layer armor;
- do not over-penetrate;
- do not generate a blast capable of damaging modules;
- do not start fires;
- have a special damage limit for large calibers against destroyers;
- are not affected by the IFHE skill;
- glow red in flight.
SAP vs. AP Characteristics
|Tier||Ship||Bounce angle||Max. Damage||Muzzle Velocity||Pen. (mm)||Bounce angle||Max. Damage||Muzzle Velocity|
|100/51||VI - X||S-1, L-20, K-1||80°-85°||2200||804||29||-||||-|
|120/45||III-IV||Nazario Sauro, Turbine||60°-75°||2600||850||34||-||||-|
|120/50||VI-VIII||Aviere, Luca Tarigo, Vittorio Cuniberti||60°-75°||2850||950||34||-||||-|
|Paolo Emilio, Adriatico, Attilio Regolo||60°-75°||3050||875||38||-||||-|
|203/50||V, VI||Genova, Trento||70°-80°||4860||840||54||45°-60°||4700||840|
|203/53||VII, VII||Gorizia, Zara||70°-80°||5050||900||54||45°-60°||4800||900|
|305/46||IV,V||D. Alighieri, Cavour||70°-80°||7850||850||79||45°-60°||8100||840|
|381/50||VII-X||Caracciolo Veneto Lepanto Colombo||70°-80°||12,500||880||96||45°-60°||12,000||850|
Armor Piercing (AP) shells trade some explosive for the ability to punch through armor. The nose of the casing is a pointed, high-density metal cap that, at least in theory, forces its way through armor plate. Because of the mass of the penetrator (the metal cap) a smaller amount of high explosive can be carried. An AP shell carries a time-after-impact fuse, to provide a short time (typically 0.033 sec) for the shell to penetrate before exploding.
The intention of the design is that an explosion inside a critical (and thus well-protected) area of the target ship is more effective than a larger explosions in a less critical area. AP shells carry out that intent well — in the right situations. Other characteristics of AP shells:
- can shatter;
- can ricochet;
- can overmatch;
- can penetrate heavy armor in the right circumstances;
- can over-penetrate;
- can damage or destroy modules by direct hit;
- do not start fires;
- have a special damage limit for large calibers against destroyers;
- glow white in flight.
The interaction of Armor-Piercing shells and heavy armor is quite complex. See the dedicated article Armor Penetration for details.
Before the first Iowa-class USN battleship was laid down, the US Navy developed the "super-heavy" 1,225 kg Mark 8 shell for its new 16" Mk.7 gun. This shell is deployed on all Tier VIII+ USN battleships for their 406mm/45 Mk.6 and 406mm/50 Mk.7, and in a larger variant (1746 kg) for their 457mm/45 Mk.1 guns.
Employing the same technology, the US Navy developed super-heavy AP (SHS) shells for its heavy cruisers. All Tier VIII+ USN cruisers (except Wichita and Anchorage) mounting 203mm/55 Mk.15, 203mm/55 Mk.16, and 305mm/50 Mk.8 guns fire SHS AP shells (152 kg and 517 kg respectively).
The secret to SHS AP performance is the heavier shell weight. The kinetic energy of a shell (or anything) is Ek = 1/2 * mass * velocity2. With the same initial (muzzle) velocity, a shell with more mass will have more energy. As a shell travels through the air, it loses energy to drag, slowing it down. The amount of drag is essentially the same for both heavy and light shells. Thus at the point of impact the heavier shell will have more of its energy left. This extra energy translates directly into better armor penetration, along with a little extra range.
In battle, SHS is functionally identical to 'normal' AP. It just hits harder.
Selecting ammo type
On the battle screen, along the bottom, the ship's ammo types appear labeled  and  with a picture of the shell above.
The HE shellhas a yellow nose and stripe. SAPhas an unpainted nose and a thin red stripe. APhas a red nose and red stripe.
To select ammo type, press the  or  key for the desired type:
- Switches to gun aiming view from such as the torpedo aiming view.
- If the selected type is already loaded, the key press does nothing else.
- If a different ammo is loaded or loading, the next load will be of the selected type. (The currently loaded ammo stays loaded for the next salvo.)
Pressing the key twice forces an immediate reload operation.
Another description can be found here.
Shell-type switching time
When the shell type is switched, each turret loads the new shell type with a reload time that we call the turret's shell-type switching time. It is equal to the ship's minimum shell-type switching time if the turret's remaining reload time (before the shell-type switch) was less than that. Otherwise it is equal to that remaining reload time.
- In other words: turret's shell-type switching time = the maximum of these two values:
- turret's remaining reload time (before the shell-type switch)
- ship's minimum shell-type switching time
The commander skill Gun Feeder reduces the ship's minimum shell-type switching time by 40% or 60%.
- ship's minimum shell-type switching time = ship's main battery reload time × FGFS × FRIB
- FGFS =
- 1 if the commander has not mastered the Gun Feeder skill
- 0.6 if the commander has mastered the Gun Feeder skill and it is not an enhanced skill for that commander
- 0.4 if the commander has mastered the Gun Feeder skill and it is an enhanced skill for that commander
- FRIB =
- 0.7 for researchable Italian battleships
- 1 for all other ships
- Without the Gun Feeder skill, the turret's shell-type switching time is equal to the ship's main battery reload time for most ships (for researchable Italian battleships: between the reload time and 0.7 × reload time).
- With the Gun Feeder skill, the turret's shell-type switching time is often lower and never higher than without it (if everything else is the same).
- When a turret has been loaded, its shell-type switching time is the ship's minimum shell-type switching time.
Which type to use?
The simplest answer is, "Load HE or SAP against ships facing toward or away from you; load AP against ships turned broadside to you."
Of course, the best answer is not that simple. There are a number of factors that influence the right ammunition choice for your situation:
- the caliber of your guns;
- the nature of your shells;
- the type of target ship, it's range and armor scheme;
- the target ship's orientation to you and how it is maneuvering;
- what you currently have loaded or loading.
Armor-Piercing shells do their maximum damage by penetrating the target and detonating inside the ship. To assure penetration, AP must hit at a nearly right angle. It is most effective against broadside targets and weakly armored target sections.
High Explosive should be used when firing at an angled heavily armored target, or when firing at a lightly armored target. HE should be aimed at the targets superstructure or bow and stern sections. HE can also be used in a strategic fashion to destroy anti-aircraft guns to decrease the danger to friendly aircraft.
SAP acts much like HE without the threat of fire or module damage. When the alternative is AP, the decision to use it is very much like that of choosing between HE and AP. For ships that use SAP and HE shells together, SAP will deal more immediate damage with more penetration while HE can start fires and works against targets too angled for SAP.
Battleshipsshould be firing AP at most targets, as those shells have the potential to do the most damage. Since they fire so few and take so long to reload, though, a battleship commander should be more aware than others of how effective a salvo will be against a particular target. For instance, a target battleship well angled would deflect his AP at the current angle. If he's turning away, the commander should wait for him to expose his broadside. However, if he shows no sign of it, the commander may want to order HE loaded and clear his tubes by firing. Or if he has the Gun Feeder skill, he may choose to order the faster forced reload.
Some battleships, notably Conqueror, have HE with a very high fire chance. The commander may prefer to load HE, but he should remember that AP in the right circumstance is the more deadly option.
Destroyers have no citadel. Compared to what battleship AP is designed to damage, they are unarmored. Battleship AP should not fuse on destroyer armor so hits (probably overpens) are limited to 1000 HP damage. Against DDs, a BB with the option should load HE.
Cruisersmost often fire HE (or SAP), unless presented with the gift of a broadside by a ship that their AP can penetrate (usually another cruiser). Against all but the best-armored destroyers, HE (or SAP) is most effective. Besides being able to penetrate their armor, destroyers are small enough that modules such as engine and steering gear are frequently within the blast volume of a hit.
Don't ignore cruiser AP, though. Even 6" AP from such CLs as Dallas can be devastating to other cruisers, especially at close range.
Destroyersdo not normally fire AP, but if presented with a perfect broadside at close range, regardless of the target's class, they should load AP. Even the 100mm guns of Akizuki are capable of landing a couple thousand damage AP salvos on a broadside battleship (particularly the superstructure).
The larger question for destroyer captains is whether to fire at all. In many ways, a destroyer's stealth is a greater weapon than its guns.
Guns and their shell types
- Most ships can fire HE or AP shells from their main batteries.
- Tier I cruisers can fire only HE shells.
- These ships can fire only AP shells: Tech-tree II-★ British light cruisers, premium cruisers VIII Tiger '59 and Hampshire, special cruisers X Gibraltar and Plymouth, special destroyer X Druid, Spanish premium cruiser VI Canarias, Commonwealth premium cruiser VI Mysore and Pan-American premium battleship VIII Atlântico.
- These ships can fire SAP or AP shells: Tech-tree II-X Italian cruisers, premium cruisers V Genova and VII Gorizia, Italian tech-tree battleships, premium battleship IX Marco Polo and US premium cruiser VIII San Diego.
- These ships can fire HE or SAP shells: Italian tech-tree destroyers and premium destroyer IX Paolo Emilio, US special cruiser X Austin and US special destroyer X Forrest Sherman.
- Submarines with controllable main guns can only fire SAP shells.
- Most secondary guns fire HE shells. The IFHE commander skill (see above) applies to shells fired from secondary as well as main batteries.
- Italian special cruiser X Napoli (B), Italian premium battleship IX Giuseppe Verdi and submarines armed with secondaries fire SAP shells.
AA ammunition is not directly modeled in World of Warships. The effects of shell size and type, rate of fire, etc. are collected into the concepts of AA auras and flak barrages.
- New type of Shell (SAP).
- ↑ 1.0 1.1 The skill is available to battleships, cruisers, and destroyers.
- ↑ For the HE penetration rules, see Armor Penetration,
- ↑ 3.0 3.1 Between the listed angles, there is an increasing chance that the shell will ricochet.
- ↑ Penetration = ((0.24908 x caliber) + 4.37966) rounded down.
- ↑ 5.0 5.1 5.2 Submarines with controllable main battery guns have only access to SAP shells.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 Tech tree Italian destroyers, FR25, Paolo Emilio and Austin fire HE instead of AP shells.
- ↑ For comparison, a light (862 kg) 16" HE shell is fired at 820 m/s. The heavy (1,225 kg) Mk.8 SHS AP shell is fired at 762 m/s. Even though initially slower, the heavy projectile possesses 355 Mega-joules energy while the light projectile possesses 290 Megajoules.
- ↑ Since British cruisers have only AP, it appears labeled . Pressing  or  has no effect on ammo type but switches to the gun aiming view from such as the torpedo aiming view .
- ↑ For more information, see this, Update 0.11.8: Changes to the Reload Mechanics or Development blog.