House Rule - Firearms

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While isolated, the cites of Langushur are more technologically advanced than many other areas of Easrae
and Wesrae. In particular, the wizards and craftsmen of the Far Shore have discovered the secrets of black powder and firearms. And a new class of warrior, the musketeer, has arisen to make use of these new-fangled weapons.

Magic users, thieves, halflings, and classes restricted to one handed weapons may use pistols. All other classes may use both pistols and muskets. Musketeers are specially trained in the use of firearms, and have certain advantages when using them as described below and in the Musketeer class description. 

At the start of the campaign, the only available firearms are matchlock pistols and muskets; other firearms may make an appearance as the campaign progresses. The matchlock firing mechanism is a lit match cord, a fuse that burns slowly. When the trigger is pulled, the match is pressed into the priming pan and the powder charge ignited to fire the gun.

Firearms
Name	Cost	Damage	Range	Weight
Pistol	75gp	1d8	25’ / 50’ / 100’	2 lb
Musket	150gp	1d8	50’ / 100’ / 200’	10 lbs

Other Equipment
Name	Cost	Weight
Powder Horn        Holds 50 shots	5gp	1 lb (empty)
Black Powder        10 shots	20gp	0.5 lb
Shot Bag        100 round shot	20gp	10 lbs
Match Cord        Per Foot	2gp	0.1 lb
Black Powder, Barrel        1000 shots	2000gp	40 lbs

Firearms - Disadvantages

A lit match cord burns at a rate of 1 foot every 6 turns; the maximum practical lengths of match cord is 3 feet. Due to the acrid odor and light, the presence of a lit match cord will make it difficult under most circumstances to surprise an enemy. Lighting a cord takes 1d3 rounds.

Black powder weapons are prone to misfiring; the powder discharges but the ball does not fire. Misfires occur on any 'to hit' roll of 1-2 on 1d20. Damp conditions double the chance of misfire (1-4 on 1d20), while wet conditions quadruple the chance (1-8 on 1d20). The chance of misfire is halved for musketeers (1 in 20, 2 in 20 and 4 in 20, respectively). After misfiring, it takes 3 rounds to clear the firearm (2 rounds for musketeers).

Firearms take 3 rounds to reload after firing (2 rounds for musketeers).

Accuracy drops off dramatically beyond short range. 'To hit' penalty at Medium and Long Range are -2 and -3 respectively.


Firearms - Advantages

All firearms do a base 1d8 damage. However, whenever a hit does maximum damage, the die "explodes". That is, another 1d8 is rolled, and this value added to the total damage. This continues as long as an "8" is rolled for damage.

Firearms are noted for their ability to penetrate the toughest of armor. When using firearms, ignore 5 AC points of physical protection (for example: armor, hides, thick carapace, etc) when firing at short range. Armor is treated normally at medium and long range.

The discharge of a firearm is a loud, odorous and flashy endeavor. Discharge of a firearm automatically forces a morale check for creatures with a morale of 7 or less. The first hit from a firearm will also force a morale check in any creatures. This may be the first creature hit in a group, or the first hit on an individual creature. There will be exceptions to this rule as determined by the DM.

Unlike other missile weapons, a pistol may be fired when the shooter is engaged in melee. Both pistols and muskets may be wielded as a club in melee.

Inspiration 

Lamentations of the Flame Princess "Firearms" Rules; Barrel Rider Games "Buccaneers and Bilge Rats";  BX Blackrazor "Bow, Crossbows and Guns"