XM8

   The XM8 is a prototype infantry weapon system. It's development commenced in the late 1990s. It was developed by the famous German Heckler & Koch company in cooperation with the US Army. The US Army required a cheaper, lighter and more effective weapon than the M16. The XM8 was developed as a replacement for the M16 family and was intended to become a standard issue weapon. First prototypes were delivered for testing in 2003. Overall over 200 prototypes have been produced, however a wide scale testing was cancelled because of the funding problems. The whole project was cancelled in 2005.

   It is a gas operated, selective fire weapon, chambered for the standard NATO 5.56 x 45 mm ammunition. The XM8 was developed from the HK G36 assault rifle into a modular system, which could be reconfigured into one of the available variants, depending on mission requirement. It is available in some baseline versions: personal defense weapon, carbine, marksman rifle and squad automatic weapon. The entire modular construction of the XM8 is built around the receiver with bolt group. Barrels and other modules can be swapped quickly, depending on operational requirements. Barrels are available in several sizes. A baseline carbine version if fitted with a 318 mm barrel. The XM8 appeared to be a reliable weapon.

   The materials used to build the XM8 are almost entirely composites. It appears to be a rugged and reliable weapon. During a "dust test" it recorded only 128 stoppages in 60 000 rounds.

   This carbine has ambidextrous controls, mounted above the pistol grip. Trigger group of the XM8 has semi-auto and full-auto settings. A cocking handle is located on top of the receiver, so the weapon can be cocked using either hand. A spent case ejection window is on the right side of the receiver. It has a spent case deflector, which propels the cases away from the left-handed shooters.

   The standard XM8 is fed from detachable 30-round magazines. However this magazine is not compatible with the M16's STANAG magazine. A high capacity double-drum magazine is available for the squad automatic weapon.

   Initially the XM8 variants had an integrated red dot 3x optical scope, however later it was changed to a 1x red dot sight. A dedicated marksman version comes with a 3.5x magnification scope.

   The XM8 has a telescopic buttstock, which is adjustable for length. This weapon is compatible with the XM320 40-mm underbarrel grenade launcher, which is an improved version of the HK AG36. It can be mounted on the current M16 and M4 firearms. Also it can be also used as a stand-alone weapon. However this grenade launcher is claimed to be inferior to the old M203.

   This weapon uses new accessory attachment system, which allows for precision attachment. It is worth mentioning that accessories planted on the Picatinny-type rails often need adjustments, if they were removed and re-attached.

Variants

   PDW or compact carbine, fitted with a 229 mm barrel and short foregrip. It has a folding stock or buttcap;

   squad support weapon (light machine gun) comes with a 508 mm barrel and integrated bipod, which folds over the foregrip. It is fed from 100-rounds double drum magazine;

   dedicated marksman rifle comes with a 508 mm barrel and integral 3.5x magnification scope.