Weapon Name- Mk. 8 Combat Rifle
Round Type- 6.8mm Remington
Over-all length- 26-40 inch (660mm - 1000mm)
Barrel length- 9-20 inch (228.6mm - 508mm)
Weight- 5.9lb - 7.5lb
Rate of Fire- 750 RPM
Feed Mechanism- Detachable Box magazine, possible belt fed
Round Capacity- 20, 28, 30, 40, 50 round drum, 100 round drum, 100+ belt fed
Effective Range- 600m
Range- 1000m
Accuracy- .75 to 2.0 MOA
Accessories- Picanty Rail
Quick switch firing mechanism- N/A
Scope/Sights- Picanty Rail
Muzzle Velocity- 750-800 m/s
Firing System- Gas-operated, rotating bolt, short stroke piston operated
Miscellaneous/electronic information- The weapon is essentially a highly remodeled XM8 designed to combine effective features of the rifle with a more effective platform.
Basic Information
The weapon is essentially a highly remodeled XM8 designed to combine effective features of the rifle with a more effective platform. The weapon essentially incorporates the XM8 firing system, or internals, and configures them to an AR-15 styled platform. The new configuration still retains all the capabilities of the old one- including the adjustable magazine holder. However, a primary a difference between the original XM8 and the new MK. 8 is STANAG Compatibility. The weapon is essentially compatible with all standard NATO magazines, despite being compatible with various other types of magazines.
The weapon is dual fed, being able to be fed typical M249 belt links from the top and standard STANAG magazines from the bottom. While excessive recoil and reliability issues from sustained fire in such a light rifle platform is usually a problem, the redesigned firing system coupled with various other features of the weapon allows for exceptional performance in raw function. While it possible for the barrel to over-heat, the SAW barrels are essentially designed to withstand the high pressures and temperatures of regular firing. The weapon was noted to be capable of firing 15,000 rounds without a single misfire, jam, or other complication without lubrication or cleaning, as quoted "PEO says the XM8 can fire 20,000 rounds without stoppages or malfunction. The first XM8 tested fired 15,000 rounds without cleaning or lubrication without a first misfire." [1] Internally, the XM8 uses a rotary locking bolt system that functions and fieldstrips like those used in the M-16 rifle and M-4 carbine. The bolt is powered by a unique gas operating system with a user-removable gas piston and pusher rod to operate the mechanism. Unlike the current M-4 and M-16 direct gas system with gas tube, the XM8 gas system does not introduce propellant gases and carbon back into the weapon's receiver during firing. While the XM8 was not exposed to battlefield conditions, it's still a feat the current service rifle hasn't come close to rivaling. During their Oct. 20-23 2003 trip to Germany, the weapons experts said they were impressed after watching Heckler & Koch engineers fire four high-capacity magazines, with 100 rounds apiece, in less than five minutes.
In July 2007, the US Army announced a limited competition between the M4 carbine, FN SCAR, HK416, XCR, and the previously-shelved HK XM8. Ten examples of each of the four competitors were involved. Each weapon fired 60,000 rounds in an "extreme dust environment." The purpose of the shoot-off was for assessing future needs, not to select a replacement for the M4. The XM8 scored the best, with only 127 stoppages in 60,000 total rounds, the FN SCAR Light had 226 stoppages, while the HK416 had 233 stoppages. The M4 carbine scored "significantly worse" than the rest of the field with 882 stoppages. [2] [3]
