This is what became of the Army's futuristic M-16 replacement rifle
The US military has long explored the idea of replacing its M-16 assault rifle with something newer and deadlier. From the 1990s onward, German arms giant, Heckler & Koch, was heavily involved in helping the US Army attempt to reach that objective, creating newfangled firearms that bear considerable resemblances to the guns you'd find in futuristic, sci-fi movies and TV shows.
The XM8 was one of these rifles developed by H&K in the early 2000s as one of a number of alternatives to the M-16 and its derivative M4 carbine. Born as a scaled-down replacement for another H&K prototype — the XM29 — the XM8 entered a limited production run in 2003, concluding just two years later.
Like the M-16 and M4 platforms, the XM8 also utilized the 5.56 x 45 mm NATO round. Built as a modular weapon and based on the G-36 rifle, then in use with the German military, soldiers could adapt their XM8s while in the field to serve in a variety of roles.
The XM8's compact variant during testing. (Photo from US Army)
A barrel swap and changing the stock could quickly take the XM8 from its carbine variant to a smaller personal defense weapon, similar in size to an MP5 submachine gun. An XM320 (now the M320, the Army's standard-issue grenade launcher) could be mounted to the weapon with considerable ease for added firepower.
If a platoon out in the field needed a ranged weapon, the XM8 could be retooled accordingly by simply exchanging the barrel for a longer one, adding a more powerful scope, and a collapsible bipod. Should the situation and scenario call for something with more sustained rates of fire, the XM8 could even be turned into a light machine gun with a rate of fire between 600 to 750 rounds per minute.
To top it off, the XM8 wasn't just light and extremely versatile, it was also cheaper to produce than the M4 carbine — the rifle it was designed to supplant. Proven to be fairly reliable during "dust tests," even when compared against the M4, the XM8 was, on the surface, the ideal replacement rifle.
US Army generals test the XM8 system. (Photo US Army)
In fact, in the latter stages of the XM8 program, even the Marine Corps demonstrated an interest in testing and potentially buying the new rifle. Should the Department of Defense have picked it up, the gun would have been produced entirely in Georgia, in cooperation with other brand-name defense contractors.
In 2005, however, the program was shelved and quickly canceled. According to retired Army General Jack Keane, a huge proponent for replacing the M4, the XM8 program fell victim to the layers of bureaucracy that typically develop in military procurement schemes. Outside of the bureaucratic issues plaguing the new rifle, there were also technical shortcomings H&K addressed very poorly.
The weapon's integral optical sight was partially electronic and, thus, required battery power. As it turns out, the original batteries for the weapon lost their charge too quickly and needed to be replaced. Unfortunately, the new batteries added weight to the rifle — the exact opposite of what the Army wanted.
A PASKAL frogman (center) wielding the sharpshooter/marksman variant of the XM8 (Photo from Wikimedia Commons)
Battery woes were the least of the Army's concerns. Soldiers would have to worry about burning their fingers on the XM8's handguards, which were very susceptible to overheating and even melting. The solution there was to also replace the handguard, adding even more weight. At the same time, unit production costs began to balloon as a result of the fixes created to refine the weapon.
While the US military was decidedly against the XM8, Heckler & Koch found a new customer overseas just two years after the XM8 program was canned. Though it didn't meet the DoD's standards for a new service rifle, the German arms manufacturer argued that it would still be an effective weapon with its kinks worked out.
As it turns out, the Malaysian Armed Forces were very interested in buying a small number of the futuristic rifles for their special operations units, namely Pasukan Khas Laut, their naval special warfare force, also known as PASKAL. By 2010, PASKAL troopers began using the XM8 to reduce reliance on their M4A1 SOPMOD carbines, alongside other H&K products like the HK416 and the G-36.