Combat/Overweight Penalty and Fit Gun Bonus

This article is Overweight Penalty/Fit Gun Bonus The article is already being adopted and currently under renovation.

Missing Information: Fit Gun table for BB, updated information and sources, quantified effects

Page Adopted By: Tsubakura Please contact this person before making any major (non-grammar, typo correction, redesigning etc.) edits on this article.

See also:

• Gun Fit Bonuses
• Fit gun bonus - Reddit intermediate players' guide

Fit Bonus and Overweight Penalty

With the introduction of fit gun mechanics on July 28th 2014, ships now will receive fit bonus/penalties depending if the equipped gun fits for the class or if the gun is too heavy for the ship to use.

As fit bonuses are unaffected by morale or combined fleets, it becomes important that you utilize the fit bonuses as much as possible.

Fit mechanics do not apply to the abyssal fleet.

Large Caliber Main Guns

Battleships receives accuracy bonuses if the guns are fit and accuracy penalties if its overweight. How much bonus/penalty a ship receives, depends on the battleship class, the caliber and type of the gun and whether the battle takes place during day or night.

Ship Class	(P)35.6cm(DC), 38cm(K), 30.5cm(K), 38.1cm (/N)	38cm四, 38cmK四	381mm, 381mmK	41cm			16inch (United States Navy)			16inch (Royal Navy)			46cm			P51cm, 51cm
				41cm, Proto, Kai	3K2	2K2	Mk.7	Mk.7 +GFCS	Mk.6 mod.2	Mk.I	+AFCT	Kai +FCR	Proto	46cm	Kai
Gangut	+7 30.5cm: +10	0	+1	-7			-3			-9~10?	??	??	-7	-18	??	N/A
Kongou Class	+7	0	-2	-5	-5?		-5	-6~7?		-5	-6	-3	-7	-10	-10?
Bismarck Vittorio Veneto Class	+4	0?	+1	-5			-5	-4?		-5	??	??	-7	-10	??
Iowa	+4?	0?	-2?	-5			0	+2					-7	-10	??
South Dakota									-5 M: +4.6
Richelieu	+4	+4~5	-2	-5			-5			-7	-14?	-8	-7	-10	??
Warspite	+6 38.1cm: +8		+1~2	+2				-2?		+5	??	+3~4	-8	-11	??
Nelson	0		0	+3?				0		0
BBV	+4	0	+2	+2			0			0?			-3	-7 F+: -11?	-4?
Ise-class Kai Ni	+4?	0?		+4?	+4?	+6						+2	??	-7 F+: -11?	??
Ise/Fusou Class Base	+2	0?	+2	+2			+2	+2?		+3			-3	-7	??
Nagato Class																0
Nagato Class Kai Ni	+2?	0?	+2?	+5	+5	+5~6	0				+4		-2?	-4?	-6?	Nagato: -5 Mutsu: -8
Yamato Class	0												+3	+3	+7	0
Note: Fit gun mechanics are still being investigated to this day, hence the values are not final and may be subject to changes. Values with a question mark either means that its not conclusive yet or the conclusion drawn here is not the same as the one drawn by yumeji. The table shows an estimated accuracy fit bonus based on having one fit gun equipped. For married ships, the overweight penalty is reduced by 40% (A married Kongou with a 46cm receives a penalty of -6 instead of -10, for example). If more than one gun of the same class is used, multiply the modifier by the square root of number of guns. (A Kongou-class with two A class guns equipped for example, that's √2 x 7 = 9.89) If guns from different classes are used together, add the modifiers together. (A Kongou with a 35.6cm and 41cm mixed for example, that's 7 - 5 = 2. Exceptions arises where different guns of the same class gives different bonuses on certain ships, notably Gangut. What would happen if you combine 30.5cm and 35.6cm is still under investigations. The information in this table is sourced from this spreadsheet maintained by Dewy with the relevant sources linked in the spreadsheet.
Last Updated: Aug 24th 2020												Made by: Tsubakura

More generally, the accuracy offset can be defined with the formula:

[math]\displaystyle{ W = \sum^{\text{All Classes}} \left ( C_{k} M_{k} \sqrt{N_{k}} \right ) \% }[/math]

Where:

• [math]\displaystyle{ W }[/math] is the resulting fit bonus or overweight penalty
• [math]\displaystyle{ C_{k} }[/math] is the main coefficient of the equipped gun class. Refer to the above table for the coefficients applied to each Battleship for their respective guns.
• [math]\displaystyle{ M_{k} }[/math] is the marriage coefficient for the particular gun class. Assumes a value of 0.6 if the ship is married, and if the main coefficient is negative.
• [math]\displaystyle{ N_{k} }[/math] is the number of equipped guns for that gun class.

Medium Caliber Main Guns

This section is outdated and needs updating. Devs have tweeted about adjusting invisible fits[citation needed], some data is outdated or missing sources. Potential misinformation.

Cruisers can receive accuracy and/or firepower bonuses from using fit guns in their load-out.

Ship Class	14cm Single 15.2cm Single ()	14cm Twin  14cm Twin Kai	15.2cm 15.2cmK	Bofors 15.2cm	15.5cm  15.5cmK	20.3cm  20.3cm(2) 20.3cm(3)		203mm/53	8inch Mk.9  8inch Mk.9 m.2
						Day	Night
CL(T)	+4N +1	??	+2? +2	+3 ??	-2 -2N	-3N?		-2 -2.5N?	-10N?
Agano Class		??	+5 +2N? +2		-2 -2N
Ooyodo Class		??	+2? +2		+2
CA(V)						0	+5 +5N?		0
Mogami Class					+2
Mogami Class Kai Ni					+5
Zara Class								+1 +1
Seaplane Tenders (AV)		-6N	-6N			-8 -10N			-8 -10N?
Note: Fit gun mechanics are still being investigated to this day, hence the values are not final and may be subject to changes. Values with a question mark means that it is potentially outdated and might no longer be correct. The table shows an estimated accuracy and/or firepower fit bonus based on having one fit gun equipped. The variable N refers to the number of guns of that category equipped. (Ex: 2 guns of 2N = 4 ACC) Bonuses from guns of different classes are simply added together. The night fit bonus from the 20.3cm series used to be capped at +15%. However, it is unknown whether this cap has been removed or not from the recent updates. There is a possibility that certain fit categories only work during the day. The possibility is plausible, but there's no concrete data proving. The alternative theory is that the night bonus from the 20.3cm series overrides any other categories. The information in this table is sourced from these two spreadsheets (1) (2) the latter maintained by Dewy, both with the relevant sources linked in the spreadsheet. As of 13th December 2018 the hidden firepower bonus of 14cm Twin Gun Mount Kai does not work/does not exist[citation needed].
Last Updated: June 23rd 2019								Made by: Tsubakura

Small Caliber Main Guns

As of June 23, Yura and Mutsuki/Kamikaze-class destroyers gain fit bonuses from having single mount equipped.

Ship	12.7cm Single HA Mount (Late Model)	12.7cm Twin HA Mount (Late Model)
Light Cruisers (CL)	+4N	+2 +2N
Yura Kai Ni	+4 +10N
Mutsuki-class	+5
Kamikaze-class	??
Unknown factors: Only Yura K2 and Satsuki K2 were tested[citation needed]. It's unknown whether the other ships in the same class would receive the same bonus or whether it only works for specific remodels. The variable N refers to the number of guns of that category equipped. (Ex: 2 guns of 2N = 4 ACC) It is unknown whether the 12cm Single High-angle Gun Mount gives a fit bonus or not. The information in this table is sourced from this spreadsheet maintained by Dewy, but has no sources linked in the spreadsheet.
Last Updated: December 5th 2018		Made by: Tsubakura

DD Fit Accuracy

Certain DDs have higher-than-expected hit rate when equipped with certain guns or sonars.

• The bonus accuracy likely takes the form: [math]\displaystyle{ \text{ACCURACY}_\text{bonus} = \text{C} \times \sqrt{\text{N}} }[/math]
  • N being the amount of equipment.

Known "C" values
Ship/Class	Gear	C
Tashkent/Verniy	130mm B-13 Twin Gun Mount	5
Fletcher-class	5" Single Gun Mount Mk.30	4
John C. Butler-class	5" Single Gun Mount Mk.30	4
J-class	QF 4.7inch Gun Mk.XII Kai	3
	ASDICs	3
Mutsuki-class	12cm Single Gun Mount Kai 2	5
Source: [1]