Notes: This is an evolutionary development of the Stoner 63 light machinegun and M-16, blending features of the Stoner, the M-60 machinegun, M-249 SAW, and M-16 assault rifle. It is a modular design that may be stripped and cleaned very easily, without the use of tools. It is very tolerant of dirt or environmental conditions, and may be fed by magazines or belts used with the original Stoner 63 series, the M-16 series, or the M-249. The Shrike has been long delayed in development, but the first production examples appeared in late 2002. It is a modular system like newer M-16s and M-4s, with the ability to use several barrel lengths, different handguards and stocks, different sight mounts, Picatinny Rails, KAC Rails, etc. There have been rumors of battle testing in the recent conflict in Afghanistan, but this is not confirmed.

Twilight 2000 Notes: This weapon does not exist in the Twilight 2000 timeline.

Notes: Also known as the Colt Model 702 or Colt Automatic Rifle, this is a greatly-modified version of the M-16A2 assault rifle, for use as a lightweight SAW and heavy assault weapon. Primary users of the M-16A2 LMG include the US Drug Enforcement Agency, BATF, ICE, the El Salvadorian military, and the Brazilian military. The US Marines also use the M-16A2 in very limited numbers. The Canadians use their own version, built by Diemaco (Colt Canada), called the C-7 LMG; this version is detailed in the Canadian Automatic Rifles section.

The M-16A2 is at its base similar to the M-16A2 assault rifle, but there are numerous differences inside and out. Internally, the M-16A2 LMG has no provision for burst fire; safe, semiautomatic, or full automatic fire are possible. The barrel is as heavy as a bull barrel, is slightly longer at 20.1 inches, but uses a standard M-16A2 flash suppressor. The M-16A2 LMG fires from an open bolt instead of the closed bolt of the M-16A2 assault rifle. From the handguards back, the LMG looks like its assault rifle cousin, but the polymer handguards are large and square in cross-section, and perforated on top to help cool the barrel. The folding bipod is very rugged in construction, and looks sort of like a derivation of a Harris-type bipod. The bipod is adjustable to a limited extent for height and cant. Attached under the center of the handguard is a foregrip. Feed is by magazine only, but any magazine which will fit into an M-16 will fit into an M-16A2 LMG, and it is quite commonly used with Beta 100-round C-Mags. The sights are essentially the same as those of the M-16A2, but calibrated to compensate for the M-16A2 LMGs slightly greater range.

Notes: After spending seemingly forever looking for a suitable squad automatic weapon (SAW), the US Army (and later, the rest of the US armed forces) decided to go with the Belgian FN Minimi. Unfortunately, the US Army (as usual) was not willing to let well enough alone, and therefore the base Minimi was modified into the M-249. While many troops seem to swear by the M-249, my personal assessment from experience is rather dismal; the M-249 of my time in the Army (I got out in 1993), was a finicky weapon prone to stoppages and as intolerant to dirt and moisture as the M-16. (This problem has supposedly been solved on newer-production M-249s, as well as on the SPW, but as with the M-16, I will probably always be skeptical of the M-249.) The M-249 was first adopted for US Army units in 1982, but most Army units didn’t see any until 1985; some National Guard units still don’t have them! Most US Marine units didn’t see them until after Desert Storm. Acquisition of the M-249 was so slow and drawn-out that the US Army even had to buy an emergency lot of 1000 Minimis straight from FN during Desert Shield.

Basically, the M-249 is a Minimi, but many changes were made to accommodate US manufacturing methods, and more (mostly inconsequential) changes were made to suit the Army brass. The front sight is a hooded post with very limited capability for adjustment to windage, and the rear sight is an aperture adjustable for windage and elevation. Newer M-249s also have a MIL-STD-1913 rail on the feed tray cover. The quick-change barrel is 20.6 inches long and very slightly heavier than that of the Minimi, but this adds more to the weight of the barrel than anything else. The original flash suppressor was derived from, but not identical to, that of the M-16A2 (which meant that the Army had no blank adapters for the M-249 for a while); this flash suppressor was later changed to an M-16A2 type. The stock is still polymer, but it is semi-skeletonized, with a buttplate and a reinforced section for most of its length. The polymer handguard is of a different shape, and the pistol grip, while originally a standard Minimi pistol grip, is now shaped more like that of an M-16A2. The M-249 also uses an upper handguard above the barrel. The M-249 was originally meant to be fed by M-16 magazines or a 200-round disintegrating link belt contained in a plastic box which slides onto rails underneath the receiver (often known as a "ham can" to grunts). Magazine feed on the M-249 is iffy at best, further enhancing the M-249’s tendency to jam, and is officially not recommended except in emergencies. The "ham cans" have a nasty tendency to simply fall off, particularly when a troop is running hard or when the M-249 is used for sustained fire. In Iraq and Afghanistan, troops began buying improved "ham cans" which don’t fall off on their own dime, as well as devising a number of jury-rigged solutions ranging from modifying the standard containers to making new ones out of canvas (usually lined with cardboard to give it stiffness). In addition, the 200-round belts in their containers tended to become unwieldy in close assaults, and many troops began to use the 100-round belts and containers devised first by special ops units for their SPWs. The folding bipod is basically the same as that of the Minimi, adjustable to a limited extent for height and cant, but is attached a little forward from the Minimi position. The M-249 can also be fired from NATO-compatible light and medium tripods and pintle mounts. The gas regulator has also been retained.

Also known as the M-249 SPW (Special Purpose Weapon) and the ParaSAW, the Mk 46 Mod 0 SPW was designed at first for US special operations units (especially the SEALs, hence the designation), and first operationally fielded in 2001. Use of the SPW later spread at first to other members of the US special operations community, and then to a limited extent to other types of US military units, particularly infantrymen conducting CQB. The SPW is a belt-feed-only weapon; the troublesome magazine-feed capability has been removed along with the parts required to allow it. The polymer stock is a standard Minimi stock, rather than the stock used on the M-249, and also has a shoulder support for use when firing from a bipod. The finish is corrosion-resistant and much tougher and more durable than that of a standard M-249. The barrel length is reduced to 16 inches (with a 15-inch barrel an option, but not often used). The gas regulator has been removed, with the cyclic rate of fire fixed at 750 rpm; this allows a skilled gunner to squeeze off short bursts and even single shots if necessary. The portion of the handguard above the barrel has been removed, along with the carrying handle and the tripod mounting interface. The SPW is literally festooned with MIL-STD-1913 rails or their mounting interfaces; an SPW generally has at least one mounted on the feed tray cover, and can also have 3 long ones on the handguard (on all sides except the top), with another pair of short rails mounted directly under the sight post. On certain occasions, special ops units will use this rail-mounting capability to produce a compact weapon with no stock and a forward handgrip attached to the rail on the bottom of the handguard. There are also rumors of special ops use of the SPW with the sliding stock of the Minimi Para, but this has not been confirmed.

Twilight 2000 Notes: In this timeline, the SAWs were procured at a much faster rate, and the later, improved SAWs came earlier. The Mk 46 Mod 0 SPW does not exist in the Twilight 2000 timeline.

Notes: This weapon was developed in 1936 to replace the BAR. The US Marines tried it but never adopted is officially, and he only official orders were made by the Dutch for use in the Dutch East Indies. Unfortunately, the Japanese invaded and the orders stopped. Unofficially, the US Army Rangers, OSS, and Marine Raiders made considerable use of the Johnson LMG, particularly in the Pacific. The Johnson was one of the few light machineguns to operate on recoil operation. It was manufactured to a high standard, but recoil is not a good operating principle for a machinegun. In addition, the Johnson required a lot of care for proper operation, something only special operations units like Rangers tended to do on a regular basis. The Johnson is fed from a sharply-curved magazine on the left side of the receiver, but it could be charger-loaded from the right, or even reloaded with single bullets one at a time. The rate of fire could be altered between 300-900 rounds per minute. Two versions were built: the M-1941 with a wooden stock and a bipod, and the 1944 with a tubular steel butt and a wooden monopod.

One further model was made: The Dror, used by the Israelis for a short time after the establishment of their country. This weapon had a tubular steel butt, a bipod, and a long barrel jacket. It was not successful under the dusty conditions in the Middle East, and was discarded after a few years.

Notes: This weapon arose from experiments in World War 1 called "walking fire." When crossing the "no-man’s land" between friendly and enemy trenches, supporting machineguns could not fire in direction of the assault for fear of hitting friendly troops. What they needed was an automatic weapon that was light enough for an individual to carry. The problem was that technology had not caught up with the concept, and the resulting weapon, the BAR, was too heavy to be considered a rifle and too light to be a machinegun. (The idea of a SAW had not been invented yet.) The standard magazine held 20 rounds; an almost never-seen magazine, designed for use against aircraft, held 40 rounds, but these magazines were always rare in the extreme.

The BAR is an extremely complicated weapon to build and maintain. This makes it slow in rate of fire and expensive to build, but it is also very tough and close to impossible to wear out. Original versions introduced at the very end of World War 1 had a selective fire mechanism that allowed semiautomatic or automatic fire (the M-1918 and M-1918A1). The M-1918A1 also added a bipod, hinged buttplate for sustained fire, and a bayonet lug. These were later modified with a dual automatic rate of fire (350 rpm or 550 rpm) and the semiautomatic fire capability deleted (producing the M-1918A2); however, the US Marines during World War 2 and Korea modified theirs back to fire semiautomatic instead of the 350 rpm ROF. (This was also done because the dual fire rate mechanism proved to be extremely complicated to maintain and prone to fouling.) Other changes included the bayonet lug, moved to the barrel from the gas block and the addition of a flash hider. (The Marines often removed the flash hider and bipod, and almost no one actually mounted bayonets on their BARs.)

The M-1922 version was designed for cavalry use, but was pretty much used as an infantry weapon; it has side-mounted swivels, no bipod (though the standard BAR bipod could be attached), and a partly-finned barrel. It is otherwise the same as other BARs.

Other countries sometimes made slight modifications of their own, and the different types of BAR are almost innumerable. By the late 1970s, no country was known to be using the BAR, but most of them survive in reserve armories or in the hands of collectors or museums.

Many decades later, the BAR went back into production in the US – this time as a semiautomatic civilian rifle. Produced by Ohio Ordnance Works, these two civilian versions were introduced at the 2006 SHOT Show, with sales scheduled to begin in June of 2007. Two versions are to be built; the A1918 (duplicating the World War 1 M-1918 version) and the M-1918A3 (duplicating the M-1919A2 version). They perhaps built better than any of the "real" BARs were, with receivers of carbonized and heat-treated 8620 cast steel, and with design and parts made on machines which are computer-controlled. These parts are then hand-assembled and fitted.

Two common nicknames for the BAR were "Bad-Ass Rifle," and "Big-Ass Rifle."

Twilight 2000 Notes: As most BARs were still in working order, large amounts of them were pulled out of reserve stocks and museums for use by the troops in their respective countries. They were sometimes modified for use as sniper rifles.

Notes: This is the squad automatic rifle variant of the standard Stoner 63A series. Two basic versions are available: a standard version with a longer barrel, and a shorter version with a shorter barrel and folding stock. Both versions are equipped with a bipod and can use any of the magazines or belts available to the Stoner 63A series. They can fire from a closed or open bolt, and are just as often seen feeding from top, "Bren-style," as from the bottom or a belt. The "Mk 23" designation shows that the primary users of the weapon during Vietnam were the US Navy SEALs, many of who fell in love with the weapon despite its shortcomings. In addition, they often swapped folding stocks with the short-barreled versions. Another name they used for the Mk 23 is the "Commando."

Twilight 2000 Notes: As with the assault rifle versions, these weapons began to show up in an improved form among SEALs and Marines during the Twilight War.