Roleplayer #14, June 1989

Ultra-Tech Weapons and Armor

Part 1 of 2

by Mike Hurst

Since GURPS Space appeared, there have been many excellent questions and comments about the weapons and armor. This article is intended to amplify on the game background and the reasoning behind it.

Arms and Society

Weapons and armor are heavily restricted in most TL8+ societies. Restrictions are particularly heavy on anything that threatens the power and safety of politicians and bureaucrats. Civilian-legal arms are quite capable of killing an unarmored man or a hostile animal, but have limited lethality against armor. Civilian possession of armor is usually restricted and often banned. Inside spaceships, if weapons are permitted at all, they are limited to those (such as tanglers, sleep grenades and needlers) that are unlikely to pierce a hull or damage vital equipment.

Weapon Power and Efficiency

Energy weapons use power cells as ammunition. One way to rate the various energy weapons presented in GURPS Space is by their efficiency in terms of power consumed. This requires figuring power per cell. Atypically, the GURPS system is arbitrary here. Power is an abstract measure, where a B cell = 1. Elucidation of the real-world equivalent of "1" is left as an exercise for the physicists among us.

The efficiencies of B, C and D cells, in terms of power delivered per unit weight, are the same. A is slightly less efficient in terms of weight, and E is much more efficient, representing a significant economy of scale.

Power Cells and Weight

A cell = .04 power unit (1/500 lb.)
B cell = 1 power unit (1/20 lb.)
C cell = 10 power units (1/2 lb.)
D cell = 100 power units (5 lbs.)
E cell = 1,000 power units (20 lbs.)

Some weapons use this power more efficiently than others (see the table on p. 4). Within any one type of weapon, though, relative efficiency is usually similar. This is handy as a guide when designing new weapons.

Improvements in Hand Weapons

Hand lasers and flamers are +1 to damage for each TL after the TL of introduction. Blasters are +2 for each TL; blast rifles are +3. Gatling lasers are +1d to damage for successive TLs; tripod flamers are +2d. Needlers have no increase in damage, but shots increase by 20 for each TL.

Who Needs These Fancy Beamers; Give Me My Old FN

Almost any 20th-century military rifle has the capability to penetrate light or medium ultra-tech armor. It does more damage measured in dice than most of the weapons presented in GURPS Space. Then why bother with high-tech weapons?

First: bullet guns are inefficient. A lot of their energy is wasted, as represented by the "blow through" rule; beam weapons do twice die damage of bullets before any is lost.

A second reason to avoid military or criminal use of gunpowder is detectability. At TL9 and above, sensor suites that will detect and pinpoint the exact location of the chemical, noise and flash signatures of any known gunpowder weapon are routine. Chemscanners (see description on p. S47) can detect a single round of unfired ammunition at 500 yards, or the firing of one round at 2,500 yards at TL9. Two scanners can triangulate the location. Note that civilian beam weapons can be located the same way by radscanners. Military beam weapons are routinely equipped with countermeasures to defeat scanners. Occasionally, guerrilla groups using chemical weapons achieve surprise against a regular force. This trick seldom works and almost never works twice. Scare stories about old-fashioned weapons are common barracks gossip, and a staple of trivid adventure stories.

A final reason is availability. For the above reasons, gun-powder weapons are obsolete. They and their ammunition require a production and transportation base that doesn't exist at TLs above 7. Surviving weapons don't have much ammunition and very few ships haul obsolete iron and lead along the spaceways. A TL8+ character has about as much chance of finding a military gunpowder weapon as a TL7 character has of finding a cedar, buffalo-horn and buffalo-sinew Turkish composite bow.

Legitimate Gunpowder Weapons

Still, there are gunpowder weapons at TL8+; target-shooting, small-game hunting and historical re-creation are all small but legitimate hobbies. Guns for these activities are typically chambered for cartridges like the caseless .20 Short, with a damage of 1d-3. Black Powder weapons are also made for re-creationists. It is actually easier to cheat and make an effective armor penetrator with a muzzle-loader than with a replica chambered for a low-powered caseless round. Materials have improved; Black Powder weapons made with TL8+ technology are +1 to damage for each TL. It is, of course, highly illegal to load a Black Powder weapon with anything that would penetrate armor.

The Standard Weapon: Lasers

Laser is the common name for the most familiar type of beam weapon. At TL7 this actually is a LASER (Light Amplification by Stimulated Emission of Radiation); at TL8+ any coherent energy beam weapon is called a laser.

The laser has no recoil, makes no noise until it hits and is so accurate that the dispersion of the shots is less than the diameter of the beam. Lasers with automatic fire capability can select damage up to RoF times damage per shot for each firing turn. Successive shots are effectively a single beam; damage is applied cumulatively to penetrating the target's DR rather than individually. The necessary skill to get the most out of a laser beam is the skill not to let it wander, dissipating its power. Use the automatic-fire rules (pp. B119-121) to simulate this. For example, a military laser rifle does 2d. Fired at RoF of 8, it fires two groups of four shots. Roll to hit for each group. A roll of five better than needed to hit is 8d. A roll of five better than needed on both groups would be damage of 16d. A roll of exactly enough would be a hit by two shots from the group, for damage of 4d. Lasers do impaling damage, so damage that gets through to tissue is doubled.

Semi-automatic lasers can't be held on target precisely enough to get the armor-penetrating bonus. The mechanical action of firing each shot is enough to disperse it. Politicians laud this. After all, no sportsman needs that sort of power to kill animals. And civilians don't need to protect themselves from armored criminals; that's what the police are for!

Autofire Modification

Any laser can be modified to fire at full automatic, at up to RoF 8. Military laser rifles are originally manufactured to fire selectively, full auto or single shot. Civilian weapons are designed to be difficult to modify to full auto. There are three levels to which a civilian laser can be modified.

First-level conversion merely makes it dump energy faster. This is a simple conversion (eight hours of work in an electronics shop and one successful Electronics/TL (Weapons, at the TL of the weapon) roll). The laser now fires full auto at RoF 8. It cannot fire less than eight shots per second unless the power cell is discharged. The first group of four shots is at -1 to the Malf number; each successive group of four shots is an additional -1. On any malfunction the laser burns out and will never fire again; it cannot be repaired. On any critical failure, it also does 1d of burn damage to the firer.

Second-level conversion takes three days and three successful Electronics/TL (Weapons) rolls. Malf number is reduced to 16, but the laser burns out only on a critical failure. On any other malfunction it overheats and takes 1d minutes of cooling time before it will fire again.

Third-level conversion takes five days and five successful Electronics/TL (Weapons) rolls. This effectively rebuilds the laser to near military specifications. The laser malfunctions only on a misfire or jam result of a critical failure. There is a 50% chance that the laser burns out completely and does 1d of burn damage to the firer. If not, it takes 1d minutes of cooling time before it can fire again. These modifications are full auto only. To install a selector switch takes one more hour and another successful Electronics roll.

Any failed roll during the conversion process adds one full day, and another roll, to the conversion. Any critical failure ruins vital components; the weapon is functionally destroyed and will never fire again.

A problem with such modified lasers is that they sometimes won't shut off. On any malfunction, one option the GM can choose is that the laser will simply keep firing until the power cell is exhausted. This should happen when it is most embarrassing and dangerous, as per the Law of Murphy.


Any laser can be "hotshotted" – modified to get a more powerful beam. Military laser rifles and heavy laser pistols can be designed for controlled hotshotting (the ultra-tech equivalent of armor-piercing ammunition). Hotshotting gets a five for two trade off; for five shots worth of power the laser does double damage. For example, a heavy laser pistol gets 12 shots from a C cell. Each shot does 2d damage. A hotshot uses five shots worth of power, so the cell would allow only two hotshots. But each shot would do 4d damage, and all the damage would be applied whether against armor or flesh.

Laser pistols, laser rifles and holdout lasers that are hotshotted bum out rapidly. On any critical failure, in addition to any other result, they bum Out and will not fire again. On any jam or misfire result, they do 1d of burn damage to the firer. Malf is reduced to 10 for every shot after the first, and any malfunction burns out the weapon. Hotshotted holdout lasers do 1d of burn damage to the firer when they burn out.

Military laser rifles and heavy laser pistols specifically designed for hotshotting (at an additional $1,000 cost) take no damage from the shot. They just use more power. Hotshotting doubles the power of each shot; fired full auto this can be devastating, but it uses up power very quickly.

Hotshotting requires an Electronics/TL (Weapons) skill roll. It takes one success and one hour of work in a shop with the proper tools to hotshot one laser. Penalties for improvised tools and facilities are up to the GM. A failure requires one more hour and one more roll; any critical failure ruins the weapon for good.

Costs and Legality for Modified Lasers

It is illegal almost everywhere to hotshot a civilian weapon or convert one to full auto; penalties range from fines and confiscation to death. In really repressive societies, the mere knowledge of how to modify a laser is illegal; anyone who demonstrates that knowledge may be executed. Electronicists pass the knowledge to each other in conversation, and hope they are not talking to a police informant. Subversive groups and illegal arms traders have been known to set up a roboticized production line for hotshotting. The penalty is much more severe than that for hotshotting a single weapon.

Any knowledgeable policeman or soldier can recognize a full-auto laser with a brief examination (roll against Beam Weapons+2 or Electronics/TL (Weapons)+3 for less than one minute; Beam Weapons+4 or Electronics/TL (Weapons)+5 for over one minute). Hotshotting is harder to detect. Examinations of under one minute are at Beam Weapons-1 or Electronics/TL (Weapons); over one minute at Beam Weapons or Electronics/TL (Weapons)+1. Of course, either modification can be discovered by firing the weapon.

Conversions require both parts and labor. Electronics engineers don't work cheap even on legal jobs. Add coverage for the possible penalties, and the rate is likely to be over $1,000 dollars a day for competent work. (Of course, there are usually cheaper workers available; their work is worth the price.) Parts for a first-level auto conversion cost $500; for second-level cost is $1,000; for third-level cost is $2,000. Parts for hotshotting cost $750.

The parts needed for modification are distinctive; in any laser-controlling culture, purchase of the parts will require licenses and bookkeeping. Purchase by anyone without a good legal reason will be difficult, and will arouse suspicion. Very competent Electronicists can use legal parts to modify lasers. Long-distance communicators, shop-cutters, ship-drives and holographic entertainment projectors all have parts that can be modified to make a deadlier laser. Any such conversion requires two Electronics rolls, one at the Weapons specialization and one at the specialization for the intended purpose of the original device. GMs can assign penalties up to -10 to either or both rolls for really unlikely conversions. A failure on either roll ruins that part.

Military Laser Rifle

This is the basic personal weapon of the military. It was introduced at TL8, and became as widespread as the flintlock musket had been in its time.

Since the working part of the laser consists of a tube two feet long by 1 1/2" in diameter, the exterior can look like just about anything. Ceremonial guards have military laser rifles built into replicas of halberds, lever-action rifles, submachine guns or anything else that pleases whim or tradition. The normal military weapon is just a tube, with stocks, sights and controls to suit the situation, mission and firing organism, This weapon is reliable. Its Malf is Ver. (Crit). This means that it only malfunctions on a jam or misfire result of a critical miss, and then only if the malfunction is verified by rolling a second critical miss. Any result except a critical miss on the second roll means that the laser does not malfunction; it simply misses the target.

With a little luck, a military laser rifle can penetrate even the heaviest unpowered armor. A burst of eight shots can do up to 16d of damage. A hotshotted laser can do 4d per single shot, but at the cost of five shots worth of power.

The accurate range of a MLR is longer than almost any firefight distance. Its accuracy rating includes augmented sights, which usually combine magnifying, automatic range-finding and low-light vision capabilities. Without these, for instance mounted in a cane as an assassination weapon, accuracy can be very low. (A cane is SS 15 and Acc 1.)

The military laser rifle is so effective that it is controlled by any society that controls personal weapons; legality is 0. (This is a change from GURPS Space.) The usual penalty for trying to smuggle one onto a spaceship is to be shoved out the airlock without a vacc suit.

Many military laser rifles are fitted with anti-theft devices. They are keyed in some way to a single person or group, and any unauthorized firing attempt will disable the weapon. "Disable" can be anything from locking out the firing circuits to exploding a charge in the stock, depending on the degree of paranoia of the owners. Disabling the anti-theft devices is an Electronics (Security Systems) skill. It can have penalties up to -6, depending on how much time and money the manufacturers have been willing to put into theft prevention. Unscrupulous arms dealers have been known to peddle stolen guns without disabling the anti-theft systems.

The price of anti-theft systems is variable. The list price of a military laser rifle includes a basic anti-theft system (-1 to skill to disable, locks out firing circuits). More elaborate systems cost $1,000 for each -1 to disable. A failed roll to disable the anti-theft system permanently disables the gun, and may have other nasty consequences.

Heavy Laser Pistol

At TL8 the heavy laser is the most common military and police side arm. At TL9+ they are less common than the blaster, which has more shots and greater average lethality. The hotshotted version of the heavy laser pistol still hangs on because of its better armor penetration. It is not as reliable as the military laser rifle; it malfunctions on any jam or misfire result of a critical failure.

Holdout Laser

The holdout laser is so easily concealable that it has Legality 0 even though it is low-powered. (This is a change to GURPS Space.) It gets five shots from one B cell or a set of 25 A cells. It is +4 to holdout, and might not be recognized even if found. It can be disguised as almost any object. Radscanners are at -5 to detect a holdout laser on a routine search, and -2 even if they are specifically searching for one.

Gatling Laser

The Gatling laser is the normal infantry-accompanying weapon of TL9+ armies, at one or two per squad. It breaks down into three 25-pound loads (gun, power system and mount) for carrying; it can only fire if the gun and power system are joined. Assembly takes two turns for one man or one turn for two. The connections are as idiot-proof as possible; the GM should require IQ or DX rolls only for those completely unfamiliar with the weapon. Firing the weapon off the mount requires a ST of 15 and is at SS 2 and Acc 4.

The squad's tactic is to advance one weapon under the cover of another; everyone in the squad carries an extra power cell for the Gatling lasers. Most military vehicles mount at least one Gatling laser; they are even more common than .50-caliber Brownings were in the 20th-century U.S. Army.
A Gatling laser, with 20d of damage per shot and up to four shots per turn, could do 80d, which would whiff most targets out of existence, regardless of armor. They cannot be hotshotted or have their RoF increased; they are already boosted to the maximum that the material will stand.

The Dinosaur Laser

The dino laser is a single-shot weapon which uses a C cell, expending all its energy in one shot. Most civilian dino lasers actually mount two C cells, allowing a second shot if necessary. However, the weapon can only fire once every two seconds, regardless of how many cells it carries. It is easy to recognize because of its huge (over 2 1/2" diameter) tube.

As its name implies, the dino laser is used for dealing with big game and hazardous large animals. However, it is a rigidly controlled weapon because it also makes an ideal anti-vehicle or assassination device. Its legality rating is 4, which seems liberal but isn't. Legality 4 means "license required – must show legitimate need," and it is very hard to show legitimate need for something that will drop a dinosaur in one shot! Unauthorized possession of a dino laser will be treated as though the weapon had been Legality 0.

A dinosaur laser is a rifle-sized weapon, weighing 9 lbs. and costing $4,000. It has SS 16 (very clumsy), Acc 12, 1/2D 4,000, and Max 12,000. It is a TL9 weapon, doing 20d impaling damage, with RoF 1/2, no recoil, and no minimum ST. At higher tech levels, it does +2 damage per TL.

Though the dinosaur laser was originally designed as a civilian weapon, its merits were quickly seen by police and military; it is now standard in many SWAT and Special Ops arsenals. Inevitably, a version with more shots was designed. Like the military laser rifle, it uses the 5-pound D cell, which takes up most of the stock. The military dino laser is Legality 0, and fires 10 shots from its D cell, still at one per two seconds. It weighs 10 lbs. and costs $6,000. Other stats are as for a regular dino laser.

(shots, damage)
Damage in hits
@ 1d = 3.5
Damage per
unit of power
BlasterC1020 shots @2d+6260  26   
Blast RifleC1012 shots @4d+4216  21.6 
ElectrolaserC1010 shots @2d+180  8   
DisruptorC1020 shots @2d+6260  26   
Electrolaser RifleC105 shots @3d+157.55.75
FlamerC1020 shots @2d  140  14   
Tripod FlamerD10040 shots @12d 1,680  16.8 
Gatling LaserE1,000150 shots @20d 10,500  10.5 
Laser PistolC1020 shots @1d  70  7   
Heavy Laser PistolC1012 shots @2d  84  8.4 
Laser RifleC1012 shots @2d  84  8.4 
Military Laser RifleD100140 shots @2d  980  9.8 
Holdout LaserB15 shots @1d-17.57.5 
Holdout Laser25A15 shots @1d-17.57.5 
Dinosaur Laser2C202 shots @20d 140  7   
Military Dinosaur LaserD10010 shots @20d 700  7   
ScreamerC1030 shots @2d+2270  27   

This article will conclude next issue.

(Back to Roleplayer #14 Table of Contents)

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