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Saturday, February 15, 2014

Firearms in Fantasy Campaigns II - Technology by era

  As I pointed out in an earlier post, when I build lists I group and stratify the elements in order to impose order on the individual list entries.  I use the same approach in analyzing  firearms in order to reduce the variables I'll need to treat in building home rules.

Era Approximate Time Period Ignition Rifling Method of Manufacture Gunpowder formula Gunpowder milling
Primitive 1200-1450 External source and vent None Hand made High variable Poor
Matchlock/Wheellock 1450-1720 Slow match/Flint, pan and vent Very Rare Made to pattern Consistent Fair to Good
Flintlock 1610-1862 Flint, pan and vent Rare Made to pattern Good quality Good to very good
Cap and Cartridge 1810-present Percussion cap and centerfire cartridge Common Factory made Optimal, smokeless Excellent

Going across the top Era and Approximate Time Period are simply labels to help the reader put the technologies into context.  Note that the eras overlap in time periods.  This represents the gradual proliferation of the technologies over the period.

Ignition is the method by which the gun is fired.  A vent is a hole in the barrel through which the flash travels to set off the main charge.  It also allows propellant gasses to escape, lowering the range of the weapon and making misfires potentially more serious.  A pan was a small chamber which held the priming charge of powder, sparks from a flint or the lit end of the slow match were applied to the priming powder, which sent a flash of fire down the vent to the main charge.  Pan's were more exposed to the weather and made firing the weapon problematic in windy and rainy or otherwise wet (at sea) conditions.Percussion caps and their descendants, center and rim fire cartridges enabled the priming charge to be combined with the propellent charge, eliminating the vent thus making the weapon longer ranged, more rugged and less prone to misfires.

Rifling is the cutting of lands and grooves inside the barrel of the weapons, which impart  spin on the bullet.  Spinning bullets have a more stable trajectory, thus flying further and more accurately.  The downside of early rifling was the extreme expense of doing the cutting before high quality machine tools.  And more importantly, rifling requires a tight fit between the bullet and the barrel.  With muzzle loaders, the tight fit made for longer load times as the weapon was used between cleanings.

Method of manufacture - this controlled not only the design but also proliferation.  Primitive firearms were tubes on a stick, each one individually built, repairing one meant building a new one.  With the rise of mass armies armed with gunpowder weapons, the firearms began to be made to set patterns which decreased logistical issues.  However just because the parts were made to the same pattern didn't mean that they were interchangeable between weapons.  Repairing a patterned weapon required filing to fit and bashing the replacement part into place.  True factory made weapons have interchangeable parts and are therefore easier and cheaper to maintain - if you have a parts supply.

Gunpowder formula - Classically gunpowder is a ratio of saltpeter, charcoal and sulfur of 15:3:2. However many formulas have been used with varying effectiveness.  The earliest Chinese formulas weren't explosive, although quite flammable.  On top of that local sources of materials and the processes used to purify them led batches of gunpowder which were less effective than they could have been.  This reduced the range of weapons charged with it and increased the chance of hang-fires and misfires.  Often catastrophically.

Gunpowder milling refers to the size and uniformity of the grains.  Initially, gunpowder was mixed by hand resulting uneven grain sizes and reducing effectiveness by up to 2/3rds.  Again this speaks to range and the possibility of misfires.

Previous posts on Firearms
Firearms in a Fantasy Setting I

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