Customizable firearms for Low TL in GURPS[]

This is a set of rules for the customization of firearms in low TL (4 and 5) for GURPS. In the Kartazia setting, they are only available for the Muerden Gunsmiths.

Enhancement Points[]

Characters repair and build firearms using the "Armoury/TL (Small Arms)" skill. The same skill is used to produce ammunition for these guns, and that includes knowledge of how to make gunpowder. In order to design new firearms, characters need the "Engineer/TL (Small Arms)" skill. On Kartazia, the TL for firearms is 4.

A character can build or design guns of his TL with the appropriate skill if his skill level is 10 or more. This includes the ability to produce and repair all weapons from the "Firearms" table at GC278.

Characters whose skill level in "Engineer/TL (Small Arms)" is 15 or more can design better-quality weapons by imbuing them with "Enhancement Points" (EPs). To repair such wqeapons, a character's skill in "Armoury (Small Arms)" must equal or exceed the Armoury skill needed to create it.

Every point by which a character's skill level exceeds 15 gives him 1 EP when designing a new weapon. Enhancement Points can be spent through the table below:

 Effect:   Cost in EPs: 
 Damage (cost per each +1 dmg)   1 
 Damage Class (from pi- to pi, or pi to pi+, or pi+ to pi++)   3 
 Accuracy   1 
 Range (Each 20% increase)   1 
 Max Range (Each 40% increase)   1 
 Weight (each 0,125 less)   1 
 RoF   3 
 Shots (less time to reload, each 2 turns)   1 
 Shots (each extra shot the gun can hold)   1 
 Lower Minimum ST   1 
 Bulk (each +1)   1 
 Recoil   1 

Every enhancement point alters the weapon's cost by 100%.

Enhancement Points have to be spent over a weapon template that's on the firearms weapon table. These indicates the weapon templates that are mass-produced in the setting, and lay-out the common blueprints that every weaponsmith studies when learning how to design weapons themselves.

Time to build[]

The time it takes to design and build a firearm is based on its weight:

Pistols: Take their "Weight" x 8 hours to be crafted, and "Weight" hours to design.
Muskets, Rifles and Shotguns: Take their "Weight" x 1.5 hours to be crafted and "Weight" hours to design.

A character can take more time to build a weapon to gain a bonus in his "Engineering" and "Armoury" rolls. Every multiplier he adds to the time to make a weapon gives him a +1 in his effective skill roll (though that does NOT increase his Enhancement Points), every 8% decrease in the time to design gives him a -1 in his effective skill (and that DOES affect the number of available enhancement points he has). The maximum bonus or penalty that a character can gain from altering the time to design or craft a weapon is 10.

Firearm Customization Example:[]

A gunsmith of Engineering/TL4 (Small Arms) skill level 22 is building a customized weapon. His skill level gives him 8 Enhancement Points (22 - 14). He is working over the template for "Wheel-Lock Pistol, .60". This weapon's characteristics are:

 Weapon   Damage   Acc   Range   Weight   RoF   Shots   ST   Bulk   Rcl   Cost   LC 
 Wheel-Lock Pistol .60   1d+1 pi+   1   75/400   3.25/0.01   1   1(20)   10   -3   2   $200   3 

He decides to spend his Enhancement Points on the following way:

  • Damage +4 (4 EPs)
  • Shots +2 (extra shots in the gun) (2 EPs)
  • Accuracy +2 (2 EPs)

The final statistics for his weapon are:

 Weapon   Damage   Acc   Range   Weight   RoF   Shots   ST   Bulk   Rcl   Cost   LC 
 Customized Wheel-Lock Pistol .60   1d+5 pi+   3   75/400   3.25/0.01   1   3(20)   10   -3   2   $200   3 

It usually takes 3.25 x 8 = 26 hours to build this weapon, and 3.25 hours to design. The final weapon cost is $200 + 800% = $1800.

Another Firearm Customization Example:[]

A gunsmith whose skill level in Engineering/TL4 (Small Arms) 21 is building a musket based on the template for the "Flintlock Musket, .75". This weapon's statistics are:

 Weapon   Damage   Acc   Range   Weight   RoF   Shots   ST   Bulk   Rcl   Cost   LC 
 Flintlock Musket, .75   4d pi++   2   100/1,500   13/0.05   1   1(15)   10†   -6   4   $200   4 

His skill level gives him 7 Enhancement Points. He decides to spend them on the following way:

  • Shots (less time to reload): -14 turns (7 EPs).

The weapon's final statistics are:

 Weapon   Damage   Acc   Range   Weight   RoF   Shots   ST   Bulk   Rcl   Cost   LC 
 Customized Flintlock Musket, .75   4d pi++   2   100/1,500   13/0.05   1   1(1)   10†   -6   4   $200   4 

It usually takes 13 x 1.25 = 16,25 hours to build this weapon, and 13 hours to design. The final weapon cost is $200 + 700% = $1600.