Country of Origin: United States

Appears in: Company and other literature as early as the mid-1980s (as far as I know).

Notes: This weapon was designed as a private venture for a replacement for the M2HB. It aimed to fix a number of perceived problems with the M-2HB, such as the variable headspace and timing, the slow loading times, the lack of dual-belt ability, and other small details. The AAI GPHMG can be fired from a tripod (NHT) or vehicle mount. The weapon has a dual-feed mechanism and is normally loaded within both BMG and SLAP belts. It also has a mount for sighting or ranging gear, a quick-change barrel, and does not require the tedious headspace and timing adjustments of the M2HB. The AAI GPHMG fell victim to budgetary problems in the US government, and did not sell anywhere else. It remains an interesting "what if."

Twilight 2000 Notes: The AAI GPHMG appeared too late for widespread distribution, but was acquired by the US military at the advice of the Chairman of the JCS. It was popular and much sought-after.

Merc 2000 Notes: This is a weapon that sold better overseas than to the US military, most notably to the South Koreans. Nonetheless, it was never a big seller.

FN BRG-15

Country of Origin: Belgium

Appears in: I first heard of this weapon in the RDF Sourcebook, and later confirmed it in mid-1980s issues of Jane's Infantry Weapons.

Notes: This is a Belgian-made heavy machinegun designed to fill the gap between the .50 machinegun and the 20mm cannon. It has a dual-feed system that gives the gunner a choice of ammunition. The BRG-15 can also be used on helicopter mounts. It cannot be fired without a vehicle or tripod mount. The BRG-15 uses the NHT and was given a hard look by US, NATO, Israeli, and other countries’ militaries, but eventually found no takers.

Twilight 2000 Notes: The BRG-15 partially replaced the M2HB in the USMC, Belgian, French, and Israeli Defense Forces.

Merc 2000 Notes: There is isolated special operations use of this weapon, but it is mostly unknown.

Uirapuru

Country of Origin: Brazil

Appears in: Jane's and company literature up to the late 1990s.

Notes: Designed to be the standard Brazilian machinegun, the Uirapuru fell victim to budget cuts and competition from cheaper imports before it could be widely produced and distributed. Built by Mekanika Industries, the Uirapuru is named after a rain forest bird and has proven to be an excellent and reliable machinegun, though a bit expensive. The weapon is simple but ergonomically built, and has a very efficient muzzle brake.

Twilight 2000 Notes: Unlike in the real world, the Uirapuru was widely built and distributed in the Twilight 2000 World.

Merc 2000 Notes: The Uirapuru enjoyed lots of sales sales to mercenaries and clandestine units.

Country of Origin: United States

Appears in: The Microgun idea has been kicked around for while; it appears in literature as early as 1982 (as far as I've been able to find out).

Notes: Also known as the Six-Pack or the Mini-Minigun, the XM-214 is s smaller version of the M-134 Minigun designed for use by ground or light vehicle-mounted troops to deliver massive amounts of small-caliber fire for defensive purposes. It is basically similar to the Minigun, except that it fires 5.56mm NATO ammunition and have various differences in layout to adapt it to tripod and vehicle use. Though rumors persist of its testing in various hot spots around the world, it is unknown whether the Microgun has seen any real combat use, and it remains officially an experimental weapon as of 2006. The Microgun has two rates of fire, and can actually be hip-fired (though it is unwieldy). Rumors say that this weapon gave the makers of the movie Predator the idea for their fictional man-packed minigun.

Twilight 2000 Notes: This weapon was type-standardized M-214 in 1992, though it was still not produced in great quantities. In an odd sort of competition, it became sort of a badge of rank for command vehicles of infantry units to be armed with the Microgun whenever possible.