CRAM Cannon

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CRAM Cannons are customizable projectile weapons. The name apparently comes from "cramming" the different kinds of pellets into the shells.

Basics of a Good Design[edit | edit source]

Typical CRAM cannons (not deck guns, see next paragraph) are designed with a large cylindrical section under the deck, connected through a narrower neck to a turret cap / gunhouse. Most of the components, especially auto loaders, pellets, and ammo boxes, are stored in the underneath section. This section is typically composed of horizontal "slices", where vertical columns of 6-way connectors are surrounded by autoloaders, which in turn are surrounded with pellets and ammo boxes. Multiple of these columns can be arranged so that each pellet has 4 connections, the most without a more advanced 3D "tetris". The connector columns are then joined together before going into the neck, where spare space can be filled with armor and gauge increasers. The final part is the turret cap, where the firing pieces, barrels, and typically most of the gauge increasers are. For the barrel, a good setup is half motor driven barrels, around a quarter recoil absorbing, and about a quarter normal (depends on ship size and CRAM gauge; normal + recoil should be equal to motor driven), then an elevation barrel on the end (or beginning). The fusing box and laser targeter can go anywhere (if you choose to use them), but near the firing piece is typical. Most cannons should at least have an inertial fuse and timed fuse. The gauge components are often in the cap because they are more durable than pellets, and the irregular shape of the cap can be more easily filled with them. For multiple barrel turrets, make sure that 6-way connectors and gauge increasers (and ideally ammo boxes, too) from different firing pieces don't touch (you can use the 4-connection gauge corners to help you prevent unintended connections), otherwise one piece can end up with all the parts.

For deck guns (turrets which don't extend below the deck) you may disregard everything but the last sentence above. Deck guns are necessarily smaller than their in-hull counterparts, and are typically viewed as worse due to how large they must get to fit many components. The fact that the entire system is exposed means that more armor is needed. Few faction designs have deck guns, with most that do being DWG ships with the deck guns as small broadside weapons.

CRAM cannons can also be hard-mounted (not on a turret). For this it is recommended to forgo the elevation barrel as that limits horizontal traverse. hard-mounted guns have the advantage of being easier to armor and harder to destroy, though they suffer greatly due to the fact they are harder to bring to bear on an enemy. The setups which work best for hard-mounts are CRAM bombs (using the bomb chute and mounted to an aircraft, facing down), mortars (use the high firing angle setting and probably add a limit to speed, facing upward), and either broadside or forward-mounted (works best on an aircraft or other forward-broadsider). Bombs and mortars typically benefit the most from an altitude fuse, while it is better for conventional cannons to use a timed fuse instead. Broadside cannons work well on traditional sailing ship designs and as a supplement to larger ships, though turrets are usually superior.

CRAM Tetris[edit | edit source]

There is an ideal tetris for each interior diameter. For a 3m or 5m wide turret area, a 3D tetris reigns supreme, but for anything larger a 2D tetris works just fine. Due to the number of connector stacks, 3x3 turrets can really only use 1 firing piece, 5x5 turrets can use 2 with the 2D tetris, but the 3D tetris works best with just 1 barrel. 7x7 has 4 connector stacks and can therefore do a dual or quadruple setup, while the 9x9 has 9 stacks and should almost always be for a triple turret. Anything larger can vary significantly. Images of each setup may be added at some point prior to the heat death of the universe. In lieu of that, here is an attempt at an explanation. Viewing the 3x3 3D tetris from the side, in the middle there is a vertical tower of 6-way connectors. Every fourth row there is an additional 6-way out to each side. Every fourth row, but in between the other ones, you can have an extra 6-way out behind and in front of the central column. Should look a bit like a thing of coral. From there, you will need to add autoloaders such that all three of their connections are available to use within the 3x3 space allotted. Fill in the remainder with pellets and ammo boxes. Except at the top and bottom, every autoloader should be fully utilized, and every pellet should have 4 autoloader connections.

Internal volume[edit | edit source]

The diameter of the shell is increased by adding gauge increasers. For a gun with gauge increasers, the diameter is:

d = 200 + 2000(1 - 0.95^g)

For a diameter and fuses, the internal volume of a shell is:

For a 2000 mm shell with no fuses, this is about 18.1.

Muzzle velocity and base kinetic damage[edit | edit source]

Base muzzle velocity scales linearly from 60 m/s at 200 mm diameter to 100 m/s at 2000 mm diameter. This can be up to doubled by using a long barrel.

Base kinetic damage is where is the muzzle velocity. The highest base kinetic damage possible is about 7247.8.

Base AP is 3, plus the muzzle velocity divided by 150 m/s.

Kinetic damage and AP can be increased using hardener pellets.

Pellets[edit | edit source]

The power of a CRAM shell is largely determined by the pellets packed into them by material boxes. There are four types of material boxes:

  • Hardener
  • High explosive
  • EMP
  • Fragmentation

Packing rate[edit | edit source]

Packing rate is equal to 0.1 per second per effective material box. Each box counts as 0.5, plus 1 for every autoloader it is attached to.

Packing density[edit | edit source]

The density is

In other words, one density unit holds pellets depending on gauge. While it is possible to pack up to 100 density, each density is only 90% as effective as the last. The effective number of pellets is approximately (the real implementation is piecewise linear rather than smooth):

For shells with multiple pellet types, the density is computed from the total number of pellets, then the effective number of pellets of each type using the number of pellets of that type. Another way of saying it is that the effective pellets are proportioned the same as the raw pellets.

Effects[edit | edit source]

Each (effective) pellet has the following effects:

  • Hardener: +100 kinetic damage per pellet, +1.5 AP per pellet.
  • High explosive: +200 explosive damage per pellet.
  • EMP: EMP damage per pellet.
  • Fragmentation: fragments per pellet. Each fragment deals 100 kinetic damage at AP 6 regardless of the main shell's stats. If more than 60 fragments would be created, the same total damage is instead distributed among 60 fragments.

Example[edit | edit source]

Suppose we have:

  • 5 volume
  • 75 high explosive pellets
  • 25 hardener pellets
  • 10 second pack time

After 10 seconds, the total number of (raw) pellets is 100, for a density of

The total number of effective pellets is

Since three-quarters of the raw pellets are explosive, three-quarters (32.9) of the effective pellets are explosive; at 200 explosive damage each this is 6588 explosive damage. The rest (11.0) are hardener; at 100 kinetic and 1.5 AP each, this is a bonus of 1098 kinetic damage and 16.5 AP.

Health[edit | edit source]

A CRAM shell has a health of

or a maximum of 8,000, reached at 2m calibre.

Reload time[edit | edit source]

Minimum reload time is

Net reload time is:

where is the number of connections between autoloaders and ammo boxes.

Barrels[edit | edit source]

Traverse[edit | edit source]

Traverse speed is proportional to the number of Motor Driven Barrels plus one and inversely proportional to the total barrel volume + 0.1. For a 2000 mm cannon, ignoring non-proportional factors, the traverse speed is about 8 degrees per second.

Fusing[edit | edit source]

Main article: Fusing