Macrocannon

A Macrocannon is considered a baseline starship weapon utilised by vessels of the Imperium. These massive cannons deployed in ranks, destroy their targets through powerful broadsides fired in volley to overwhelm their enemy in a barrage of destruction. Macroweapons are giant, house-sized weapons covered with gantries, cranes, power lines and pipes with a crew hundreds strong.

Operation
Located upon the gun decks of spacefaring vessels, projectile-firing macrocannons require much larger crews to handle and load their enormous shells into the waiting breaches. Macrocannon crews also have to contend with sitting on top of a magazine full of enough munitions to level a city. Many captains still prefer the reliability of macrocannons despite the medieval toil they inflict on the crew. Even after suffering punishing damage, macrocannons can still load and fire long after energy weapons fall silent. Macrocannons tend to be mounted in individual gunrooms to contain the damage if their magazine explodes. Each gun is run by a gun captain and each gun deck by at least one petty officer. An ensign or lieutenant has nominal charge of the gun deck but are seldom be seen off the command decks and heard only as a disembodied voice over the vox casters.

Imperial Weapons

 * Disruption Macrocannon - This macrocannon variant fires a "shell" of highly charged, ionized deuterium atoms. These particles cause minimal physical damage to their targets. Instead, they are intended to overload and shut down power transfer systems throughout the target vessels. These weapons are particularly useful for vessels that need to capture their prey intact.
 * Hecutor-Pattern Plasma Macrocannon - The Hecutor-Pattern plasma battery is an ancient variant of plasma macroweaponry that refocuses the power of the plasma "blast," concentrating it into a compressed photonic packet that can be fired over extremely long distances. It is rare to see these on any but the oldest vessels, meaning many are found on heretic vessels lost to the forces of Chaos millennia ago.
 * Mark VI Mars-Pattern Macrocannon - The most common macrobattery, these are reliable, hard-hitting weapons that fire kilo-tonne ordnance, mounted along the vessel's dorsal ridge or in a broadside.
 * Stygies-Pattern Macrocannon - This variant of the macrocannon is designed to fire heavier ordnance than the Mars Pattern. These alternative shells contain an adamantium core that cuts through the heaviest armour.
 * Thunderstrike Macrocannon' - An older version of the Mars Pattern, these macrocannons lack range and power. They are most often found on transports.

Ork Weapons
Ork starships are more heavily armed than Imperial vessels of comparable size. Massive batteries of macrocannons dot the hulls of every Ork ship, turrets and barrels protruding from every gap in the ship's hull, capable of battering through a ship's void shields and ripping chunks out of their hull. In a matter of minutes, an Ork vessel can unleash thousands of shells at a target, filling the void around an enemy with debris, shrapnel and unexploded shells. Above all other weapons, Orks favour massive shell-hurling macrocannons, referred to collectively as "Gunz." Grouped together into batteries, these weapons fire volley after volley of solid shot and explosive shells, overwhelming any enemy in a torrent of destruction. However, these guns don;t always work as desired, sometimes misfiring or jamming. They may also be deactivated for repairs or "improvements" by a bored Mekboy. The following is a list of the most common "gunz" found aboard Ork spacefaring vessels: quickly become inaccurate over long range. Nevertheless, they cause terrifying damage at close range. Often rebuilt from the largest broadsides of Imperial Cruisers, these guns protrude menacingly from the scowling armoured prows of kroozers, ready to unleash salvoes of heavy explosive shells. Kannonz often have extra-long barrels, so the shells fire further.
 * Gunz - The most common Ork macrobatteries are referred to as Gunz. Though this encompasses any number of different types of weapons, most fire projectiles of some sort or another. It's fairly common for Orks to loot weapons from defeated vessels, so many guns are "improved" versions of Imperial macroweapons. The Ork inclination towards firepower is such that any gap in the haphazard armour plating is soon filled with a gun.
 *  'Eavy Gunz - Alongside more conventional macrocannons, the Orks commonly employ short-ranged but extremely powerful guns. Firing dense slugs of scrap metal massing thousands of tonnes, as well as a jury-rigged plasma bombs, these shells

Eldar Weapons
The Eldar disdain using shells and crude warheads on their starships, preferring elegant and deadly laser and plasma-based macrocannons. These potent weapons are devastatingly accurate.