GURPS Rules additions

High Tech Ballistic Warfare

A number of GURPS products, such as Vehicles 2d. Ed. discuss the special rules governing projectile weapon ammunition. However, few (if any) of these books also discuss the influence of these technologies on high technology societies. Here, we will attempt to (very briefly) address this and propose some rules modifications to "officially" balance things out. First a summary of what the rules say and what it means, and then what to do about it.

HEAT - High Explosive Anti-Tank: Rules: Armor Divisor of 10, except Laminate which is only 5.
Meaning: Vile and vicious penetrating power. Extensive deployment makes Reactive Armor Plates an absolute must, but otherwise, there are no real defensive improvement until TL11 when Thermal Superconducting Armor becomes available (double effective DR against HEAT).
HESH - High Explosive Squash Head: Rules: 1/10 of all damage rolled automatically penetrates the DR of the target, regardless of the DR.
Meaning: Really nasty, huh? And as the rules currently read, there are NO defenses to offset this effect. So, obviously, the greatest danger to a TL14 world-building species with nuclear damper technology is a punk TL7 species with HESH warheads.
Note: In an e-mail, David Pulver told me that GURPS Ultra-Tech 2 contains the following rule addition /clarification/correction for HESH: "If HESH's basic damage fails to penetrate DR, apply 10% of the damage against 1% of the DR." [Guess I'd better get myself a copy of UTT ;-) ]

Well, for every great offense, there is eventually a great defense. It seems reasonable that each Tech Level uses a slightly different mechanism to achieve the same effect. This would be the natural evolution of warfare, and would work well with the game mechanics.

To protect our star-sprawling empires from the humans, we use the following rule additions:

Force Fields completely negate the special damaging properties of HEAT and HESH warheads, regardless of any Explosive damage that penetrates the Force Field DR.
Laminate armor that is one Tech Level higher, or any armor two or more Tech Levels higher than the Tech Level of the warhead completely ignores the special damaging properties of HEAT or HESH. This means that TL8 laminate armor, and any armor TL9 or higher is resistant to the special properties of TL7 HEAT and HESH warheads, while TL9 HEAT will penetrate any TL9 or lower armor.
See also this page.