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Advanced Cannons, or Advanced Projectile Systems (APS), are even more customizable than CRAM Cannons, at the cost of maximum shell size.

Currently being reorganised and expanded.

Cannon components[ | ]

An advanced cannon system consists of two main parts, the cannon itself, and ammunition production.

Firing Piece[ | ]

Main article: Advanced Firing Piece


The Adv. Firing Piece is the Core Block of the cannon itself. The number of barrels can be selected from one to six.

  • Overclocking: A cannon can "borrow" up four seconds of cooldown. Once this time is used up, the cannon returns to its normal sustained rate of fire. Recoil and inaccuracy are multiplied by a factor (1 + overlock seconds used), i.e. up to 5x.

Mantlet[ | ]

Main article: Mantlet


A mantlet goes directly on the front of the Advanced Firing Piece. It determines the traverse range of the barrel. The first, lower number corresponds to what a 500mm gauge, while the second, higher number corresponds to a 50mm gauge.

Mantlets count as 1m in barrel-length – If you'd need a 5m barrel for propellant burn, it's sufficient to use a mantlet and a 4m barrel.

Mantlet Azimuth in ° Minimum elevation in ° Maximum elevation in °
Omni Mantlet (1m) 10 to 30 -10 to -30 10 to 30
Elevation Mantlet (1m) 5 to 20 -20 to -40 20 to 40
Omni Mantlet (3x3m) 40 to 60 -40 to -60 40 to 60
Elevation Mantlet (3m) 5 to 10 -45 to -65 45 to 65
AA Mantlet (2) 5 -5 to -15 80 to 100

Multiple barrels results in an additional effective gauge for the purposes of traverse range:

Number of barrels 1 2 3 4 5 6
Extra gauge (mm) 0 500 450 600 650 650

Traverse range is always at least 5 degrees in each direction. Cannons can be built without a mantlet, in which case this is their traverse range.

Barrel[ | ]

Main article: Barrel (APS)


Barrels go on the front of the mantlet. More barrels increase accuracy, and may be required to achieve maximum muzzle velocity for a given amount of propellant.

The cannon's Q-menu allows to split these to allow for multi-barrel setups. This decreases the gauge. Each barrel cools down independently, allowing a higher maximum rate of fire.

For a barrel length and barrels the traverse per second is

Note that this does not apply to heavy barrels. These have lower traverse speed, but unknown how much lower exactly.

  • Barrel
  • Heavy Barrel
  • Bore Evacuator
  • Muzzle Brake

Gauge Snake[ | ]

  • Gauge Increase (APS)
  • Gauge Increase Right Left Splitter: The forward end must go towards the Firing Piece.
  • Gauge Cooling Unit: Cooldown time is multiplied by 0.92 for each Cooling Unit.

Gauge Increases go behind the Advanced Firing Piece. Gauge refers to the diameter of shells that are fired from the cannon. For a single-barrelled cannon, the diameter starts at 60 mm. The first Gauge Increase adds another 60 mm; additional Gauge Increases are each 0.98 times as effective as the last. The cap is 500 mm at 8 Gauge Increases.

Having multiple barrels will divide the gauge by 20/10 for 2 barrels, 20/9 for 3, 20/8 for 4, and so on.

Gauge Increases Barrels
1 2 3 4 5 6
0 60.00 30.00 27.00 24.00 21.00 18.00
1 120.00 60.00 54.00 48.00 42.00 36.00
2 178.80 89.40 80.46 71.52 62.58 53.64
3 236.42 118.21 106.39 94.57 82.75 70.93
4 292.90 146.45 131.80 117.16 102.51 87.87
5 348.24 174.12 156.71 139.30 121.88 104.47
6 402.47 201.24 181.11 160.99 140.87 120.74
7 455.62 227.81 205.03 182.25 159.47 136.69
8 500.00 250.00 225.00 200.00 175.00 150.00
Cooling Units Seconds to cool
1 2 5
0 1 2 5
1 0.9200 1.8400 4.6000
2 0.8464 1.6928 4.2320
3 0.7787 1.5574 3.8934
4 0.7164 1.4328 3.5820
5 0.6591 1.3182 3.2954
6 0.6064 1.2127 3.0318
7 0.557847 1.1157 2.7892
X 0.92^X*1 0.92^X*2 0.92^X*5

Ammo[ | ]

  • Autoloader: These go on the sides of the Advanced Firing Piece or Gauge Increases or next to each other. Each Autoloader can hold one cartridge ready for firing.
    • Belt Feed Autoloader: Fires 5 times as fast as a conventional 1m autoloader, but cannot fire and reload at the same time, and cannot start firing until 6 seconds after its clip is full.
  • Ammo Clip: These go on the sides, top, or bottom of Autoloaders, or the top only of Belt-Fed Autoloaders. They hold cartridges ready for loading.
    • For cartridges of up to 250 mm gauge, one ammo clip holds cartridges in two stacks.
    • For cartridges of greater than 250 mm gauge, one ammo clip holds cartridges in a single stack.
  • Ammo Input Feeder: These go on the front or back of Autoloaders or Ammo Clips. These transfer cartridges from the supply to the clip.
  • Ammo Ejector: These go on Autoloaders. When an associated ejector, autoloader, or clip is destroyed, instead of detonating, all associated shells will be ejected at a speed of 50 m/s, plus a random value of up to 15 m/s along each axis. This prevents the propellant from detonating. An Emergency Ejection Fuse makes this completely safe, otherwise the shells can still trigger inside your craft.

Stored ammunition explodes when an autoloader or clip is destroyed. Powder modules do 20% as much damage as flak modules for this purpose, but are computed separately from true flak modules.

Railguns[ | ]

Railguns use electricity to increase the velocity of the fired shells. The increased velocity also increases the kinetic damage and AP.


This article is a stub. You can help From the Depths Wiki by expanding it.

  • Railgun Magnet Attaching Feature: Attaches to the side of the Firing Piece.
  • Railgun Barrel Magnet: Attaches in a line to the Attaching Feature. Analogous to Laser Destabilizers. The first magnet discharges a base of 2% of stored energy per shot, with subsequent magnets discharging 0.9 times as much as the last. For magnets, the proportion discharged per shot is
  • Railgun Charger: Attaches to Gauge Increases, Gauge Coolers, or Connectors. Each charger provides 100 charge per second times the railgun overclock, and each unit of charge costs energy equal to the railgun overclock.

Ammunition Production[ | ]

Ammo Controller[ | ]

Main article: Ammo Controller


The Ammo Controller is the core component of ammunition production.

Ammo Customisers[ | ]

Main articles: Ammo Customiser, Ammo Customiser Single Module


Ammo Customisers go in a line in front of the ammo controller. Each customiser adds two shell-modules – A single module customiser allows to make shells with an uneven number of modules, often allowing for another module without exceeding the Autoloader's length. The maximum amount of shell modules you can have is 20, regardless of shell diameter.

Strategy and Examples[ | ]

Cannon-Design[ | ]

Shell-Design[ | ]

Choosing a Shell-Type[ | ]

If you don't know what to pick: Fragmentation will work in almost any situation. HESH is another good choice – better vs thick armour, but unusable for airburst.

Other shell-types are more special-purpose.

Shell-Type Shorthand Calibre Main Purpose Airburst-Capable Shields Notes
Armour Piercing AP Above roughly 80mm
HP works better below 80mm
Low-calibre: General-purpose
High-calibre: Dealing damage behind armour quickly
No High chance of getting reflected, due to high velocity Large AP-shells may deal overkill damage, and exit the target with kinetic damage to spare
"AP" includes sabot, see optimisation
Hollow Point HP Any Beating thick armour
As head on payload-shells, to make use of their kinetic damage
No High chance of getting reflected, due to high velocity Impact-fuse – detonates on contact with a block, but not on shields or water
High Explosive HE High calibres
Works best above 400mm
General-purpose Yes, but loses damage quickly Low-velocity may pass shields
Explosion itself ignores shields, behaves like airburst
Fragmentation Fr
frag
Any General-purpose
Low-cone F can be used to pierce armour, at the cost of raw damage
Yes Low-velocity may pass shields
If triggering on a shield, the fragments will spawn behind it, but may be deflected by shields behind the first
There's a limit on fragments in the game – exceeding it will reduce overall damage
Flak High calibres As CIWS-shell, to kill missiles Yes Low-velocity may pass shields
Explosion itself ignores shields, behaves like airburst
Near-useless against almost all vehicles, due to low damage
Electromagnetic Pulse EMP Works best at high calibres Special-purpose to take out AI, and other blocks vulnerable to it No Low-velocity may pass shields Ignores most kinds of armour almost entirely
High Explosive Squash-Head HESH Any
Low-calibre possibly due to unintended behaviour
Dealing damage behind armour No Low-velocity may pass shields Impact-fuse – detonates on contact with a block, but not on shields or water
High Explosive Anti-Tank HEAT Best at medium-high calibres
Above around 100mm
Dealing damage behind armour and shields Yes, at up to 50m distance Practically ignores shields, when fused Lower damage than HESH, but harder to avoid its post-penetration damage
HEAT-head has an impact-fuse – detonates on contact with a block, but not on shields or water
Disruptor Conduit DC
Disruptor
Works best at high calibres Special-purpose to take out shields No Triggers on shields, even without a fuse Near-useless against unshielded targets
Vulnerable to LAMS
Armour-Piercing High-Explosive APHE High calibres, above around 400mm Dealing damage behind light or medium armour Practically no High chance to get reflected, due to high velocity
Damage if triggering on a shield would be too low to be worth the fuse
Far greater post-penetration damage than HEAT or HESH, but far less reliable and easier to counter
Can use F instead of HE

Maths[ | ]

Scary numbers to optimise shells and cannons further, or design things without opening the game. None of the following is necessary to design effective cannons.

Shell Design[ | ]

To avoid confusion with the consumable resource "ammo parts", we will refer to the items in a cartridge as "modules".

We will refer to the entire collection of modules as the "cartridge" and the modules minus the casing as the "shell". Let be the number of modules in the cartridge, and be the number of modules in the shell.

Modules[ | ]

Each module is a cylinder with diameter specified by the shell diameter in metres, and length equal to the diameter. The volume of a cartridge is then

Likewise, let be the volume of the shell (projectile) only.

Category Module Speed modifier AP modifier Kinetic damage modifier Maximum length (mm) Detectability Factor Description
Casing Railgun Casing 1 1 1 1 Increases velocity from railgun charge by 50%. Additional railgun casings past the first are each 90% as effective as the last.
Casing Gunpowder Casing 1 1 1 1 Determines muzzle velocity. More casings mean higher velocity. Also increases cooldown.
Shell Rear Only Graviton Ram 1 1 1 1 Uses the shell's recoil to inflict a pushing force on the target it hits. Speed of the shell is also a factor in how much the target gets knocked back.
Shell Rear Only Base Bleeder +0.15 1 1 100 1.1 Increases Speed modifier by 0.15 but multiplies the inaccuracy by 1.35
Shell Rear Only Supercavitation Base 1 1 1 100 1 Removes water drag entirely, as well as the chance to bounce off the water's surface. Reduces EMP damage, explosive/flak damage and radius, and frag count to 75%. Useful when trying to take out submarines, or adding guns to a submarine.
Shell Rear Only Visible Tracer 1 1 1 100 1.5 Improves accuracy by a factor of 2 for a few seconds after firing. Bonus reduced if shell-velocity differs.
Shell Middle Frag Warhead Body 1 0.1 1 1 Creates a cloud of shrapnel on detonation. Multiplies shell health by 0.5
Shell Middle Solid Warhead Body 1.1 1 1 1 No special effects, most useful for kinetic shells
Shell Middle Sabot Warhead Body 1.1 1.4 0.8 1 Increases AP and decreases KD. Reduces EMP damage, explosive/flak damage and radius, and frag count to 25%.
Shell Middle HE Warhead Body 1 0.1 1 1 Deals explosive damage. Multiplies shell health by 0.5.
Shell Middle Grav. Compensator 1 1 1 100 1 Shell is always affected by at least its starting gravity. This lets the shell take the aimed trajectory when firing into orbit. Also doubles time before drag sets in, making high-angle guns more viable.
Shell Middle Flak Warhead 1 0.1 1 1 Deals less explosive damage than the HE warhead body, but in a larger radius. Shell health is multiplied by 0.5.
Shell Middle Smoke Warhead 1 0.1 1 1 Creates smoke on hit, provided the shell is at least 200mm in diameter. Smoke follows vehicles if the shell impacted on the vehicle. Useful to silence enemy LAMS or lasers. Multiplies shell health by 0.5.
Shell Middle Inertial Fuse 1 1 1 100 1 Detonates when deflected by a surface (material, shield, water). Deflection angle to trigger can be set.
Shell Middle Proximity Fuse 1 1 1 100 1 Detonates the shell at a set distance. Only checks directly in front of the shell – usually not a good choice. This module has been removed from the game.
Shell Middle EMP Warhead 1 0.1 1 1 Deals EMP damage. Multiplies shell health by 0.5.
Shell Middle Stabiliser Fin Body 1 0.95 1 300 1 Multiplies inaccuracy by 0.2 each. Slows down the shell.
Shell Middle Altitude Fuse 1 1 1 100 1 Detonates at a set altitude. Can be set automatically when using a Laser Targeter (APS).
Shell Middle Timed Fuse 1 1 1 100 1 Detonates at a set time after firing. Can be set automatically when using a Laser Targeter (APS).
Shell Middle Penetration Depth Fuse 1 1 1 100 1 Detonates at a set time or depth after first impact. Depth only counts blocks (air does not count).
Shell Middle Emergency Ejection Fuse 1 1 1 100 1 Prevents detonation if the shell is ejected. Needs an ejector on the loader to work.
Shell Middle Shaped Charge Secondary 1 0.1 1 1 Uses all HE modules behind it as a second shaped charge warhead. Allows penetration of ERA. Multiplies shell health by 0.5.
Shell Nose Only HE Head 1.45 1 1.2 1 A HE warhead with better stats for the nose of the shell. Multiplies shell health by 0.9.
Shell Nose Only Disruptor Conduit 1.6 1 1 1 Shield-killer. Reduces EMP to 25%. Needs 125 listed EMP per shield strength to kill the shield in one hit (i.e. 1250 for a max-strength shield). Reduces strength of all payloads to 50%. Changes shell health by a factor of 0.9.
Shell Nose Only Squash Head 1.6 0.1 0.1 1 Turns the shell into HESH, using all the HE just behind the head. Shell health changed by a factor of 0.9.
Shell Nose Only Frag Head 1.45 1 1.2 1 A frag warhead with better stats for the nose of the shell. Changes shell health by a factor of 0.9.
Shell Nose Only EMP Head 1.45 1 1.2 1 An EMP warhead with better stats for the nose of the shell. Changes shell health by a factor of 0.9.
Shell Nose Only Heavy Head (earlier AP Capped Head) 1.45 1 1.75 1 The standard head for most kinetic shells. Provides moderate AP with high kinetic damage.
Shell Nose Only Armor Piercing Head (earlier Composite Head) 1.6 1.65 1 1 Increased muzzle velocity and AP compared to the Heavy Head but decreased kinetic damage.
Shell Nose Only Skimmer Tip 1.6 1.4 1 1 Doubles maximum angle of incidence at which the shell bounces off water. Guaranteed to bounce off the water if within the incidence angle. Highest speed-modifier amongst all non-sabot modules.
Shell Nose Only Flak Head 1.45 0.1 1 1 A Flak warhead with better stats for the nose of the shell. Changes shell health by a factor of 0.9.
Shell Nose Only Sabot Head 1.6 2.5 0.85 1 Reduces EMP damage, explosive/flak damage and radius, and frag count to 25%. Has the highest AP and speed of any module however. Changes shell health by a factor of 0.9.
Shell Nose Only Shaped Charge Head 1.6 0.1 0.1 1 Uses all HE modules behind it to blast a stream of superheated copper into the target, creating HEAT damage. Changes shell health by a factor of 0.9.
Shell Nose Only Hollow Point Head 1.45 1.2 1 1 Spreads all kinetic damage laterally as thump damage.

Ballistics[ | ]

Muzzle Velocity[ | ]

Let be the number of propellant modules.

Let be the length of the gunpowder casings, be the length of the shell without the casings and be the length of the whole shell (all in metres). The muzzle velocity from propellant is:

is the speed coefficient, defined below.

Projectiles inherit the velocity of the cannon they are fired from, and this affects all velocity-dependent characteristics, namely AP and kinetic damage.

Once in flight, projectiles are affected by gravity and drag in water (but not air). However, this does not change AP or kinetic damage.

Railguns[ | ]

For a charge expenditure of and railgun casings, the muzzle velocity is increased by

Railgun casings increase this by a factor

Speed Coefficient[ | ]

A factor in muzzle velocity is the speed coefficient, which is a weighted average of the speed modifiers of the (non-casing) parts, where each component starting at the head has half the weight of the previous:

The head will thus always determine at least 25% of the speed coefficient.

For example, suppose the shell has a Composite Head (speed modifier 1.6), a Solid Warhead Body (speed modifier 1.3), and a Supercavitation Base (speed modifier 0.9). Then we have

(Since 2.3.3.1 s=s1+(0.10248*(summ(s)-s1))/(ns-1)

Propellant Burn[ | ]

The length of barrel needed for optimal propellant burn is

If the barrel is too short, muzzle velocity will be reduced proportionally.

Effective Time[ | ]

The time a shell will travel before suffering drag is

Ammunition and Reloading[ | ]

Effective Number of Modules[ | ]

Generally the effective number of modules is used rather than the actual number of modules in the maths since some modules count as less than one module. Casings only count as one quarter of a module and modules that have a maximum size (i.e. fuses) can count as less than one module.

If is the number of gunpowder casings, the effective number of modules is:

Ammo Cost[ | ]

Filling Ammo Clips[ | ]

This is the reload time of a particular shell. Specifically, after this many seconds pass, each Input Feeder checks whether it can reload its associated autoloader. If there is space, the Input Feeder moves one cartridge from the supply to the autoloader's clips. Otherwise, it retries every second.

  • Input Feeders may be attached directly to the Advanced Firing Piece. Feeders attached like this will reload an available clip or autoloader but only if that autoloader is attached directly to the firing piece; it will otherwise act like a normal direct input feeder if this is not the case. If the Firing Piece has no autoloaders, it can hold one cartridge ready for firing.

Loading[ | ]

This is the equation to find the RpM of an advanced cannon, this value should be set in the main firing piece to prevent the gun from burst firing. Let be the number of autoloaders attached to the firing piece and be the number of faces of the autoloader with a clip attached.

This is the equation for the "seconds per shell" (the time that passes in between each shell being fired):

  • If beltfed autoloaders are used set the number of clips in the RpM equation to as this will account for the beltfed bonus; the RpM given will be for the "firing phase" of the autoloaders.
  • If an autoloader has no clips, is 0

Barrel Cooldown[ | ]

The base barrel cooldown of a particular shell is:

Let be the number of coolers. For a single barreled gun the overall cooldown time is roughly:

The exact equation for the above isn't yet known, nor is the equation for multiple barrels or bore evacuator.

Recoil[ | ]


This article may need updating to the game's current version. Use information provided here with care.
Please help improve this if you can. The Discussion page may contain suggestions.
Reason: "Absorbers now reduce recoil by a set amount, and have to regenerate; Missing info on muzzle break"

Let be the total length of Hydraulic Recoil Absorbers. The displayed recoil is

The units are kN frames, and currently depend on game speed.

Inaccuracy[ | ]

Let be the length of the barrel, including all variants as well as the Mantlet. Let be the length of the shell (ignoring casings) and be the length of the casings (all in metres). Then inaccuracy for a single barrel is:

Now let be the number of barrels on the gun. For more than one barrel the inaccuracy equation is:

If a base bleeder is used then the final inaccuracy is multiplied by

If railgun charge is used to boost accuracy, the accuracy is improved by a factor of

[citation needed]

Health and Detection[ | ]

Shells have a health of times any modifiers from modules.

Detectable range is times any modifiers from modules, times a factor from firing altitude. This increases linearly from 1 at 10 m to 4 at 400 m.

Damage and other hit effects[ | ]

AP[ | ]

Let be the AP coefficient of the shell.

If the shell has fewer than 3 modules, the missing modules are treated as having an AP modifier of 0.5.

Kinetic Damage[ | ]

Let be the kinetic damage coefficient. Unlike the speed and AP coefficients, this is an unweighted average.

If the shell has fewer than 3 modules, the missing modules are treated as having a kinetic modifier of 0.5.

The kinetic damage is then

HE Warheads[ | ]

For HE modules (count Shaped Charge and Squash Heads without HE modules as half a HE module), the explosive damage is approximately

and the radius is

Note that all explosives have a hard cap on radius of 30m.

EMP Warheads[ | ]

For EMP modules, the EMP damage is approximately

Flak warheads[ | ]

For flak modules, the explosive damage is approximately

and the radius is

The flak effect is completely separate from any HE effect. All explosives have a hard cap on radius of 30m. Note that flak can "snap" onto a target-vehicle that is within its radius, and will then deal damage within 30m from the closest point. Also, the cap only applies to blocks - missiles and the avatar can be damaged at any range.

Fragmentation warheads[ | ]

The number of fragments is

and the total damage of all fragments is

[1]

Where is amount of modules, and is the frag cone angle in degrees. Fragments have AP 6.

Squash heads[ | ]


This article may need updating to the game's current version. Use information provided here with care.
Please help improve this if you can. The Discussion page may contain suggestions.
Reason: "HESH now generates spalling in several places in a semi-circle in front of it; unknown if formulas are still accurate"

Spalling metric is

where is the total special factor of all HE warheads, counting the squash head itself as 0.5.

Upon hitting a surface the squash head ejects damaging particles on the opposite side. The number of particles is equal to the spalling metric divided by the number of AC-metres passed through.

Each particle does 200 damage and has AP equal to twice the armour of the last material passed through.

Thump damage is

and is applied at AP 10.

Shaped charge head[ | ]


This article may need updating to the game's current version. Use information provided here with care.
Please help improve this if you can. The Discussion page may contain suggestions.

For penetration factor , penetration metric is

and particulate count is approximately

where is the total special factor of all HE warheads, counting the shaped charge head itself as 0.5.

Regardless of the values shown in the customizer, the actual penetration factor is always between 0.05 and 0.95, and the actual special factor for HE warheads cannot be less than 0.01.

Each particulate deals 200 damage at AP 10.

Graviton ram base[ | ]

Each point of kinetic damage converted produces 100 kN s of impulse. The translational component of the force may be converted to torque using the slider.

Trajectory[ | ]

Skimming[ | ]

On reaching within 0.25 m of the surface of water, a shell has a 50% chance to skim (reflect) off once provided the shell is travelling no more than from horizontal. This instantly reduces the velocity of the shell by 10%. Some shell modules induce different behaviour:

  • A shell with a Supercavitation Base will never skim unless it also has a Skimmer Tip.
  • A shell with a Skimmer Tip will skim up to 1000 times with 100% probability, and the maximum skim angle is increased to .

Drag[ | ]

Shells are unaffected by drag when in air, until reaching their effective time (as listed in the Ammo Customiser screen). In water, they slow down exponentially with an (instantaneous) deceleration rate of 70% of their velocity per second. Shells with a Supercavitation Base ignore underwater drag.


  1. https://www.desmos.com/calculator/tpszdpyzo5/ | I know this is a bad citation, someone should probably fix this. also, someone should check my work, the equations don't work when module count is high (~50 modules)
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