Country of Origin: United States

Appears in: This weapon was developed for SEAL use in Vietnam, but was not adopted.

Notes: During 1966-67, the SEALs and other US special operations forces tried several designs in an attempt to increase the firepower of their grenade launching systems over the M-79. One of these systems, which never received any official designation, was a triple-barreled grenade launcher designed to be carried under the M-16 and CAR-15. This design used a slide-forward loading design in a similar manner to the then-experimental underbarrel grenade launcher, the XM-148, but improved to prevent dirt from entering the mechanism and eliminating the guide bar system of the XM-148. The trigger mount is similar to that of the XM-148, however. The barrels are shorter than that of the XM-148 or M-79, being only 6 inches, to allow it to fit under the CAR-15 without projecting beyond the barrel. At least three and as many as five of these launchers were built; one was known to have been sent for combat testing to Marine Force Recon in Vietnam, while the rest were sent with the SEALs. The firepower was well thought of, but that was the only thing they liked about the design. The launcher was unwieldy, unbalanced the rifle it was mated to, and the complex firing mechanism did not stand up to the dirt and mud common in Vietnam. In fact, when the trigger was pulled, there was about a 50/50 chance that the round would not fire. The design remains an interesting, though flawed and failed, attempt to increase firepower.

Country of Origin: United States

Appears In: Current US weapons development programs

Notes: Though the XM-25 might be called a "weapon that isn’t – yet," I have included here, for the time, since due to budget pressures, the XM-25 may never make into service. The XM-25 is a child of the XM-29 OICW – it is the grenade launcher component, upsized into a weapon using 25mm grenades that are related (but not the same) as those of the XM-307 OCSW. As such, the XM-25 is an advanced, "next-generation" support weapon – and one whose real-life price is quite high. Field testing and deployment dates have repeatedly slipped and are continuing to do so; currently, no one is really sure when (or if) the XM-25 will become an operational weapon.

The XM-25 uses an external design similar in appearance to that of the also ill-fated XM-8 assault rifle; it is a smooth, sleek, lightweight polymer shell. The XM-25 uses a bullpup design instead of the XM-8’s sliding-stock design, with a recoil pad on the buttplate. Feed is by a polymer 8-round magazine; case ejection may be set up for left or right-handed shooters. Many of the metal parts are of the XM-25 also made from light alloys, with heavy steel being kept to a minimum (such as the barrel and other high-wear parts).

Atop the receiver is an advanced target acquisition/fire control sight, incorporating a thermal imager/optical sight (with 2x magnification for both), powered direct-view optics (called under the Twilight 2000 v2.2 rules an image intensifier), a laser rangefinder, and a compass. The data that the sight provides is tied together by a ballistic computer; this computer computes a fire solution, sets the fuzes of the rounds about to be fired, and then presents the information to the shooter on a unified display inside the sight. The shooter can accept the provided fire solution or modify some or all of it as necessary.

The XM-25 might be simply an advanced, rather small-caliber grenade launcher, were it not for the equally-advanced ammunition fired by the XM-25. Initially, the XM-25 was to use the same ammunition as the XM-307 OCSW, but due to the higher power of the XM-307’s ammunition, infighting between Alliant and General Dynamics (working on the XM-307), and repeated delays in the XM-307 itself, a compromise was made. The fuzes of the XM-25 and XM-307 are identical, and the warheads are almost identical (though the warheads of the XM-25’s ammunition are a little smaller). The case and propelling charge, however, is quite a bit smaller than that of the XM-307, with a 40mm-long case being used. This drops the velocity (and range) of the XM-25’s ammunition quite a bit (it’s considered a low-velocity round), but it makes the recoil manageable and still provides the XM-25 about double the effective range of the M-203.

The fire control system of the XM-25 not only sets the fuze of the grenade’s warhead to explode at the proper range, but also (depending on the target and warhead) the proper height above the target (in the case of the HEAB or Thermobaric rounds). This gives the XM-25 the "Airburst" portion of its designation – the grenades are meant to be primarily used to explode above the heads of their targets, causing the maximum damage to entrenched or exposed troops, soft-skinned troops and materiel. (This is actually still an ongoing problem with the XM-25 and its ammunition – getting the fire control computer to properly set the fuzes.) The airburst abilities of the ammunition means that the small 25mm grenade is able to cause damage equal to or greater than the 40x46mm round currently used by most of the world’s 40mm grenade launchers. The ammunition can also be set for point detonation (on contact with the target) or point detonation delay (delaying the detonation a few milliseconds, in order to go through a window or doorway) if desired or if the computer has a glitch or damage and cannot be used. The rounds shown below are those currently being tested; in addition, two training rounds have also been designed. A flechette round is also possible in the future, though as far as is known, none have yet actually been built; likewise, a tactical CS round is also possible for the future.

Twilight 2000 Notes: Needless to say, the XM-25 is not a weapon that exists in the Twilight 2000 timeline.

Country of Origin: Czech Republic

Appears in: Czech weapons catalogs of the 1990s and early 2000s.

Notes: This Czech grenade launcher is part of a family of weapons, including the B-10 assault rifle, B-20 battle rifle, and B-30 sniper rifle. Many of the components of this weapon are interchangeable with the B-30, and it is claimed that the weapons may be interchanged by simply changing the barrel and magazine.

The B-40 and its brethren seem to have been confined largely to arms shows where the designers hoped for sales which pretty much never happened, and by 2006 it was no longer being offered.

Country of Origin: United States (for Traveller purposes, Aslan)

Appears in: Space Gamer Magazine, in an article by William A. Barton (though I have changed the story considerably).

Fictional Notes: The original article for the Explosive Scatter Gun is a weapon for the original Traveller game, a Tech level 10 weapon designed by the Aslan for use against armored transports and personnel dressed in heavy battlesuits. However, this weapon can easily be imagined as something that was come up with by the likes of DARPA or China Lake, for use as a heavy grenade launcher to attack light armored vehicles, unarmored vehicles, and troops in the open. I have devised special ammunition for it, since the original weapon is described by Mr. Barton as using Tech level 10-11 RAM grenades; these are essentially higher-tech versions of NATO 40mm HV ammunition.

The XM-192 Explosive Scatter Gun exists only in the Merc 2000 timeline, and not in the Twilight 2000 timeline. It was designed for use by special operations, airborne, air assault, and Marine units for use as a heavy support weapon; fully-loaded, it is quite a handful, and while due to its advanced construction materials it is not too heavy, it is a very bulky weapon. It resembles a short rocket launcher, some 850 millimeters in length, and the barrel cluster some 105 millimeters wide. The XM-192 has a bipod near the muzzle, a forward handgrip for hip firing (which is a practice that is not recommended when burst firing), and a curved, padded shoulder stock that allows the weapon to be supported on the shoulder easily. The XM-192 uses 30mm grenades which are rocket-assisted to increase range and velocity. The weapon is fed by 10-round cassettes; the XM-192 breaks open like a shotgun at the breech of the barrel cluster. Due to the size of the cassettes, reloading the XM-192 takes 3 combat phases. (A cassette weighs 1 kilogram, plus the weight of the ammunition within; it costs $10) The "receiver" of the weapon is topped with a MIL-STD-1913 rail; the normal sight, included in the cost of the weapon, is an electronic sight similar to that used on the OICW.

The weapon may be fired in one of three ways: semiautomatically, in "half bursts" where half the ammunition in the cassette is fired at the same time with one pull of the trigger; and a "full burst", in which all the ammunition in the cassette is fired simultaneously with one pull of the trigger. Though the rocket-assisted ammunition takes up part of the recoil (the rocket fires within a few milliseconds after leaving the barrel, with a small launching charge actually firing within the barrel), the simple fact is that the recoil is brutal when half bursts or full bursts are fired. However, the half and full busts can do something a single shot cannot do – open up an armored vehicle like a can opener. Due to special enhancements to the sight and ammunition, the rounds in a half or full burst will all hit in roughly the same spot if desired by the gunner; this mode is set by the gunner by flicking a switch before firing the burst. If the gunner scores a hit, the user of a burst in this precise mode may multiply the penetration what would be a single round by 3 for a half burst, or 6 for a full burst. If a miss is made in this precise mode, all the rounds fired in the burst miss, and eventually hit the ground at their maximum effective range, scattering normally. Of course, such precise burst may also be fired at targets other than vehicles; if fired at troops in the open in this mode, scatter is rolled normally, but the maximum amount of scatter is only 1 meter. Without the precision mode, shots at troops in the open scatter normally, and shots against armored vehicles and suchlike hit as normal (enhanced by the electronic sight).

The XM-192, due to the way it fires and its effectiveness, is generally known to troops who use it as the "Splat Gun" or "Can Opener."

*Halve recoil (rounded up) and add 20% to the range when used from the bipod.

Appears in: Various weapons literature of the early-to-mid-1980s.

Country of Origin: Switzerland

Notes: The Falconet was conceived in the late 1970s as a special assault and defensive weapon for infantrymen. Designed by the likes of Francois Brandt (son of Edgar Brandt, that genius of mortar design), the Falconet appears to not have achieved any sales beyond demonstrators, nor employment in even small numbers (or possibly any numbers whatsoever).

Relatively light in weight, the Falconet employed small-caliber grenades of only 24mm in diameter, two types of grenades were contemplated, an offensive grenade with an HEDP warhead and a defensive grenade packed with 12 heavy tungsten flechettes. The grenades were to have been stabilized by fins and by the distribution of weight in the grenade. Operation was by blowback, employing a reciprocating barrel to help absorb recoil as well as a multi-baffle muzzle brake. (Its straight-line profile also helped in this respect.) For carry purposes, the barrel can also be telescoped back to the muzzle brake to provide a more compact package (though it cannot be fired in this configuration). Magazines were to be of light alloy, and coincidentally appeared similar to those of the later Barrett M-82 series. Leaf-type iron sights were to be standard, though a mount for optical sights was provided; the Falconet was intended to be a relatively direct-fire weapon.

Twilight 2000 Notes: The Falconet was employed in small numbers by Swiss and Austrian units; some captured examples were also deployed by other countries, the reports say that NATO special operations units were using them as far away as the Middle East.

Merc 2000 Notes: The Falconet suffered the same fate as it did in real life.

*A Falconet normally has a Bulk of 7. In its folded configuration, it has a bulk of 6, but it cannot be fired when folded.

*Penetration of the flechettes against vehicles is 1/1/0/0.