[3e] Statting a CTA weapon

[GURPS Fox]

Originally Posted by Varyon

The link requires a login to access. If you can provide the caliber (looks like 45 mm) and either mass of the projectile alone and muzzle velocity, or simply muzzle energy, you can get a decent-ish estimate on GURPS damage with the equation Douglas Cole worked out, where average damage in points (divide by 3.5 to get damage in dice) is equal to 0.6*SQRT(KE/cal^0.4), with KE in J and cal in mm. I think he may have mentioned before that it wasn't quite right for cannon performance, but I may be misremembering.

But what about the ammunition? Like how to stat the weight, cost, and volume of a CTA round?

I can do the damage figures. The problem here is the ammunition's weight, cost, and volume modifiers. For example, if I want to make a CTA gun, what modifiers are needed?