The Poudre Guild
Orichalcum is a magical alloy, composed of metals representing the four elements, the aether, and the twelve sacred processes held secret by students of alchemy. Each small sootblack pellet of the stuff is also highly unstable, reacting unfavorably all the classical elements, who reject this upstart chemical's claim on the world. In the right concentration, though, carefully applied through springs and wheels and other gubbins, a man might forge a weapon which produces orichalcum spontaneously - just long enough to ignite. If channeled into, say, a long pipe, it might eject any contents of that pipe out into the world at lethal force...
The Poudre Guild controls the secret of orichalcum, or as it's known to most star-wolves, gun-poudre. The liquids which marinate a burning match-wick, the slow fire of its quiet march towards ash, the metal of the pan, the iron of the barrel, even the lead of the ball are a tightly-held secret formulae. Experiments to reverse engineer this secret have been catastrophic. For the time being, the Poudre Guild retains significant control over the waging of war. The Guild functions as a secret society and occasionally as a religion; rumors speak to powerful factions and cults of personality within the group. It otherwise transcends national and planetary boundaries.
Arquebuses are not totally standardized. They are still pieces of individual craftwork. Each tells a story.
Attacking with an arquebus requires a Dexterity check of 3d6 to hit rather than a typical attack roll - the user needs to roll equal to or below their Dexterity to land a hit.1 Damage as a Heavy weapon, but with d8s (use the highest of 2d8). Heavy armor ignores results of 1-4. Medium armor ignores results of 1-2. An arquebus requires a full minute to reload; specialized trainers might reduce this to 30 seconds. Effective range is limited to one or two hundred yards.
An arquebus costs 75sp. Each shot (including wadding, poudre, and shot) costs 4sp. A bandolier holding a dozen shots counts as an inventory item and costs 3sp.
Cannons use the Firepower stat of their ship to attack.2