Freelance Traveller

Light Duty Line-Throwing Tool

by Les DeGroff

This was the winning entry in Freelance Traveller Contest 2008-04, and originally appeared on the Freelance Traveller website in 2008. It has been lightly edited and reprinted in this form in the September/October 2016 issue.

The Mark 18, TL10 Hand held, light throwing tool is found throughout Imperial space (and almost identical models, deliberately designed to take the same ‘ammunition’, can be found in the various human states bordering the Imperium) and with a variety of rounds can serve in diverse locations including space, in forests or jungles and in and on water environments. In many locations with high restrictions on weapon possession, the Mark 18 slips through a loophole as a non-weapon tool. In spite of this, a hit with a bolt, explosive setting head, harpoon or free bar can kill.

The Mark 18 and its generic cousins are not easily concealable, as they have a 30cm-long, 2.5cm-wide barrel, and typically a spool holder of about 15cm diameter and 10cm wide under the barrel. The mass of the unloaded device is approximately 3kg. A variety of cable types are available but very common is a 3mm diameter line with a standard spool holding about 250 meters of line. This material has a tensile strength of around 1000kg (and a working load of about 600kg).

Ammunition for a line thrower appears similar to blank (non-projectile) 2.5cm shotgun rounds and is available with an amazing number of different loads from pop caps that will launch a plastic sticky round at a centimeter per second up to high loads that can send a kilogram harpoon or bolt down range at 300 meters a second. It is also common to find flare, smoke flare and illumination rounds designed for the unit. Loads used in space, for pushing cables or connections between tend to the low side while hunting and forestry uses are higher power.

Range in space tends to be the limit of the line in a spool; on planetary surfaces, friction and gravity tend to limit range, with high power loads only good for a couple hundred meters.

Device prices tend to be similar to shotguns, 100 to 500 credits but propellant charges are expensive, 1 credit each for set loads, 10 credits each for higher technology variable loads. The rare sets manufactured for corrosive environments can run 20 times the price of a standard unit. Simple harpoons, piton and cable pulling projectiles run about 12 credits and are generally reusable, more specialized projectiles such as those containing sensors and electronics up into the hundreds each. Explosive placement and bomb harpoons are not reusable; most glue heads are also consumables. Line spools are about 50 credits empty, and line costs vary by the technology from fractions of a credit per meter for conductor, fiber optic and simple cables or ropes up to 20 credits per meter for high technology super cable and sensor embedded wires.

One of the nice features of a Mark 18 is that it can hold 6 propulsion rounds in a grip magazine with one in the chamber however each projectile must be seated against the seal manually. Multiple projectiles and cable spools are generally carried on a utility harness described in more detail in the accessories section below.

Frequently Encountered Bolts and Heads.

In many cases, bolts are light and sabot-ringed to fit the barrel. The weapon has a positive action seal or collet to hold one round in place. The most commonly encountered bolts and heads are given, but this list should not be considered exhaustive.

1. Marine harpoon, barbed head, stays connected to line
2. Detach harpoon, barbed head, frees from line at some predefined force
3. Bomb or explosive harpoon. In addition to barbs of head connected to line, an explosive charge is include to wound or kill large organisms.
4. Tagging harpoons. These come in a variety of sizes from delicate ones for implanting trackers in small game, to heads that can monitor large organisms for years, thousands of kilometers. Variety of release forms, quick detach, programmed delay, signal delay. These heads are generally not reusable.
5. Piton or anchor pin bolts
6. Explosive head Piton or anchor pin bolts
7. Glue squish heads, several types of glue chemistry, these are designed to stick to impact surface without penetration. Sizes range from couple centimeters to expanding units with deployed heads of over a meter diameter.
8. Fiber optic and conductor pulling heads
9. Throw-over bolts, intended to be shot over targets so the line falls to where it can be secured
10. Super injector rounds
11. As mentioned above flare, smoke, incendiary and illumination rounds. Many have parachutes for hang time. At TL11 and above units may have anti-gravity or maneuver units built in.
12. Flashlight/LED mounts on squish or barb heads
13. Monitoring sensor heads. These also include infrared, ultraviolet, and visible-spectrum remote cameras.
14. Rocket assisted heads, additional range but not more than double on planetary surface.

Available Cable Spools

As with the bolts and heads, these are the most commonly encountered spools, but this list should not be considered exhaustive.

1. 1mm super tensile, encapsulated woven monomolecular, Typical spool 800 meters, TL11 and above, requires special fittings for connections. Tensile strength 4000kg but susceptible to kink and nick damage reducing the rated values a lot.
2. 1mm fiber optic communications; typical spool 1000 meters, TL9, Tensile strength 50kg
3. 2mm 4-pair twisted communications wire (silver or copper); Typical spool 750 meters, TL8, Tensile strength 50kg to 100kg.
4. 3mm standard, woven high performance; Typical spool 250 meters but some go to 325, TL10
5. 3mm macro coated molecular filament with fiber optic pair and three conductor strand included. 2500kg test. TL10
6. 4mm high flex plastic rope, TL10, tensile of 500kg. Typical spool of 125 meters but elongation up to 100%
7. 5mm standard, woven high performance fibers; Typical spool 100 meters, TL9. Breaking strength 1500kg. Suitable for climbing safety, line crawlers.
8. 5mm high voltage three-conductor insulated wire. Typical spool 80 meters with 50cm bare of insulation at both ends.
9. 5mm, “Stiff Stuff”, chemically treated fibers become rigid on exposure to environmental conditions, (moisture in some environments, exposure to vacuum in space, air in other cases)

Common accessories

1. Vests and holsters to carry device, rounds, spools and heads. Because of bulk of the line spools, a holster with weapon, two spools and ammunition is often taken as a low technology computer or communications unit bag.(45 cm tall, 12 cm wide, 20 cm front to back)
2. Optical and electronic sights, with range finding and projectile trajectory estimation are common but pricey 1500 credits.
3. Special crimpers and connecting hardware
4. Heads up display caps for sensor, monitor and camera heads.
5. Folding or extending stocks, like most hand arms, adding a stock so it can be braced against body greatly improves possible accuracy.
6. At high tech levels, a system of line pulling rounds with a drone style controller handset and heads up display (CrImp 3000)