Firearms rules for the Greylands Campaign

The world (still unnamed come to think of it) in which the Greylands is set, being a loose distortion of our own world during its Renaissance and Early Modern period, makes fairly widespread use of black powder firearms.

While most of those are still found primarily within the ranks of mercenary companies and the occasional standing army unit, their proliferation among the semi-criminal class of people with mercurial loyalties (ya know, adventurers) is also notable, since their unreliability at long range, but comparative deadliness in close quarters is excellent for the type of people who regularly fight in small underground corridors and rooms.

On a more meta level, I feel like firearms being present is an important element in anything drawing inspiration from our real world history and set after the mid 1400s (and sometimes, earlier). I am not the only one too, as how to handle firearms has had almost as many takes as what to do with the Thief.

Below is my current idea on how to approach them, though whether this will survive contact with the campaign, I would not hazard a guess. I can be quite fickle that way.

Firearms General Rules

Easy to Use: Unless otherwise noted, any class can use firearms, although more diminutive folk like gnomes or halflings might struggle with the heavy musket.

Slow Reload: All firearms require a full round to reload, similar to a crossbow.

Unreliable: An attack roll with a firearm that rolls a natural 1 to 5 not only misses, but causes the gun to misfire, clogging it up and requiring a full exploration turn to clean out and reload.

Susceptible to Chaos: Guns really do not appreciate being around the unstable energies of Chaos. When in an area of particularly high levels of Chaos, an attack roll of 1 does not just misfire, but instead the firearm explodes, dealing 2d6 for pistols or 3d6 for arquebuses and muskets to everyone within a 10 ft range.

Inaccurate: Greylands firearms are not the tool of choice for marksmen. They get the usual +1 to attack rolls when in short range, but get -1 at medium and -2 at long. 

Penetrative: If maximum damage is rolled when someone attacks using a firearm, the dice explode, meaning you roll another damage die of the same type. If that one also rolls max damage, keep going until it doesn’t. This ability does not function against enemies wearing Plate armor (be it a full suit of plate or just partial one) or monsters with equivalent resilience and toughness (up to the Referee's discretion). 

Specific Firearms, Ammunition and Others

Pistol (wheellock)

Missile Weapon, one-handed.

Cost: 30 gold 

Range: 5'-25'/26'-50'/51'-90'

Damage: 1d8

A rare and hard to find weapon from the top engineers of the Blessed Empire's corelands, reserved for important members of the military or rich mercenaries. The current height of firearms tech, does not require one to light a wick in order to shoot! Due to their rarity out among the border territories this can be very hard to find and requires payment in gold coinage, rather than the standard silver. 

Biggest upside? Can be used one-handed and can be fired even when you are engaged in melee.

Arquebus (matchlock)

Missile Weapon, two-handed.

Cost: 60 silver

Range: 5'-50'/51'-100'/101'-140'

Damage: 1d10

The standard firearm that most people in the setting would have at least heard of if not had the misfortune of interacting with. Big and bulky guns, hard to aim and hardly precise, but capable of devastation above what most bows or crossbows are capable of, and very easy to train someone on how to shoot it. 

Musket (matchlock)

Missile Weapon, two-handed.

Cost: 120 silver

Range: 5'-70'/71'-140'/141'-210'

Damage: 1d12

The heavy arquebus, most commonly known as the musket, is quickly becoming the primary weapon of choice for the more well-off mercenary companies fighting the wars between the Blessed Empire and its neighbors of the Southern Kingdoms. Bigger, heavier and deadlier than the arquebus, the musket might frankly be overkill in a dungeon, but sometimes you just want the biggest boomstick around.

Due to its size, bulk and length the musket automatically makes the wielder one step more encumbered.

Ammunition Pouch, Lead

Ammunition

Cost: 10 silver for 20 shots 

This contains enough black powder, lead projectiles and other stuff necessary for 20 shots of any firearm. Usually carried in an oiled pouch or a horn to keep it dry, as any moisture making contact with the black powder renders it useless until dried.

Ammunition Pouch, Silver

Ammunition

Cost: 30 silver for 20 shots 

A specialty item used almost exclusively by adventurers. Similar to regular ammo pouches, but the projectiles are made out of lumps of silver rather than lead. Useful for shooting at...well anything that requires a silvered weapon. The high price is due to scarcity and inability to make the silver ammo using a home shot making kit.

Shot Making kit

Toolkit

Cost: 60 silver

A kit composed of the tools required to melt and shape lead shots by yourself out of whatever scrap lead you can find (say, by digging it out of the person you just shot). Requires downtime and access to a fire to be useable, but can save you a lot on buying ammo (though you still need to buy the black powder). 

Why isn't everyone using this? Well, these are quite rare to find outside of armies or mercenary companies, and not everyone knows how to make the tools necessary. Plus local authorities tend to look down on people being able to make their own ammunition.