Rules for Percussion Weapons

[worst2first]

I'm working on a scenario set in the early to mid-1800s and would like to know if any of the books contain rules for using percussion (cap and ball) weapons? It seems that most of the books set in the American West are based in the 1870s or later. I'll modify the Gaslight or Classic firearms rules myself if I have to but don't want to re-invent the wheel if there is already something out there. I'd also be interested if anyone has developed their own house rules for these types of weapons. Thanks in advance.

[NeferSutekh]

There is a section in the Fatal Experiments supplement that covers the Black Powder Gun skill, with a few example weapons going back to the 18th-century. I have used it before with one of my own scenarios.

[chicklewis]

I would simply lower the malfunction numbers to around 90. But I haven't checked out the Fatal Experiments approach.

[Zarozinia]

I don't really understand the details of differences between guns I'm afraid, so I don't actually know what percussion weapons are (I'm none the wiser even after having read the wikipedia page!), however, Issue 2 of Worlds of Cthulhu magazine included rules for the Old West by Frank Heller (translated by Bill Walsh) in an article called The Good, the Bad and the Utterly Insane.

It includes rules for older blackpowder weapons using percussion caps such as the Colt Navy revolver, including rules for whether you've loaded it properly and for 'overcharging' your weapon for extra range and damage (with the risk of the weapon exploding!).

If this is along the lines for what you're looking for, I've just checked Innsmouth House and they have a copy of the magazine in stock.

[Arlecchino]

I'm not sure how much difference there would be between an black powder cartridge and one with loose percussion caps. I'm no expert but from what I understand percussion cap weapons simply omitted the brass (in some cases paper) cartridge that held the shell together. The loose powder, slug, and percussion cap (a small impact triggered incendiary that provides the "spark") are all loaded seperately in the chamber. Smokeless powder and spitzer bullets weren't developed until much later so I don't think there would be much difference in the weapon's performance - just reload times.

[Sevastopol]

I ended up reading a silly amount on cap & ball weapons for a Supernatural campaign I ran that was set in the Old West. I figured that at least some of the guys were going to end up becoming gun nuts (in or out of character), so I wanted to have a firm grasp on the different types of revolvers, rifles etc available during that period. I did draft house rules for using cap & ball weapons, but I kept it simple; much longer reload times compared to using cartridges, a skill test to reload in combat/riding a horse and a higher chance of malfunction (a reflection of how fiddly reloading could be).
You could get really bogged down trying to recreate accurate rules for using any type of firearm, but I think unless you want hyper-realism you might as well keep it simple. On the other hand being able to speak with confidence about the different guns the players could end up carrying or coming across can really add flavour to a game.
"Do you want to carry a Colt Navy like Rooster Cogburn in True Grit or a Remington New Model like the preacher in Pale Rider?"

[worst2first]

Thanks for all the replies. I don't want to get too bogged down but we have one player in our group who is combat and gun play oriented. I think I'll start by lowering load times, accuracy and range and increase the malfunction chances.

[SpitfireIX]

Another issue is that black powder weapons tend to create a large amount of smoke, especially when there's little or no wind. So after several rounds have been fired there should be additional penalties to hit, as there will likely be clouds of smoke in between firer and target.

[Arlecchino]

While it's true that black powder does create a lot of smoke when discharged, the only times that I've read that it caused issues with visibility is in battle field situations with several soldiers firing at once. I wouldn't impose penalties unless there were a lot of weapons firing repeatedly and/or there is little to no airflow or ventilation.

[Aviatrix]

A lot depends on the historical period; cap and ball was the predominant form of ammunition in the 40 years or so leading up the Civil War; after the war, there was a rapid conversion over to brass cartridge weapons.

Roughly, going from memory, it would look something like this:

~1820-1840

Cap and ball becomes the dominant ammunition system, replacing flintlocks whenever possible.

Most handguns remain single shot. Double-barreled pistols and even rifles exist, but are rare--the extra weight makes them less useful.

During this period, "pepperbox" multi-barrel, short-range pistols become popular, but they are unreliable and hard to aim.

Colt's first revolver appears at the end of this period.

1840-1865

Revolvers become the most common sidearm. A typical model is the .36 Colt "Navy" pistol. Smoothbore muskets are replaced by rifles whenever possible. The first brass cartridge weapons appear at the end of the period, first in buffalo rifles, then in the Sharps carbine and Henry rifle of the Civil War era. Immediately after the war, Smith and Wesson and Remington introduce the first mass-produced brass cartridge revolvers.

Spot rules:

Going by CoC 6, reload rate for muzzle-loading weapons is 1 shot every 4 rounds. If we use the rule from one of the Keeper's companions (not handy at the moment), investigators with the relevant skill of 50%+ could halve that reload time. (A well-drilled Civil War soldier was theoretically capable of 3 shots a minute, so that sounds about right.)

Pepperbox would do damage as a derringer, with a malfunction number of at least 95, possibly higher. One way would be to give it a MN of 90%, and on 95% the dreaded chain fire would happen--all six barrels go off at once. Roll the total damage for all rounds in the weapon, apply it to the gun (call it 8 hp) and the rest to the hapless investigator. A successful Dodge or Luck roll could halve or eliminate the damage.

Cap and ball revolvers came in roughly the same calibers as their more modern equivalents. Damage was about the same, but I'd reduce the base range by 5 yards or so. (Handguns were generally poorly sighted and hard to aim; a good Mechanics roll could potentially adjust for that.) MN should be universally 95 or so; on a 00, a revolver chain-fires, as above.

Reloading a revolver was a painfully long procedure--many cavalry troopers during the Civil War carried multiple revolvers rather than attempt to reload them in combat. I'd say at a rough guess, it would take a round to reload each chamber, minimum two rounds (it takes some time to get the kit out, etc.) Unlike reloading a long arm, an investigator probably couldn't Dodge while reloading. As above, higher skill could potentially reduce the reload time.

Revolver-rifles existed, but were not popular; not only was the mechanism more complicated, on a chain-fire they had a nasty tendency to shoot the firer's left arm off For the most part, longarms remained muzzle-loading during the period.

Note that following the Civil War, many existing weapons were converted from cap and ball to brass cartridge; you especially see this with popular weapons like the Colt Navy or the army's Springfield Musket. Eventually, though, it got cheaper to just buy a new weapon, especially from 1872 on, when the Colt Peacemaker was introduced.

NB, this is all based on my research into the period (I had an Old West kick a couple of decades ago.) Folks who have actually used cap and ball weapons are free to rip this all to shreds