Weapon Name- Hk416
Round Type- 6.5mm Grendel
Over-all length- 25.5-28.5- 30-33 inches, 35.5-38.5
Barrel length- 10 inches, 14.5 inches, 20 inches
Weight- 6.5 lb, 7.5 lb, 7.9 lb, 8.2lb
Rate of Fire- 600 RPM
Feed Mechanism- Detachable Box Magazine, Belt Fed, Drum magazine
Round Capacity- 30, 50, 100, 100+
Effective Range- 400, 500, 600 Yards
Range- 1100 yards
Accuracy- 2 MOA, 1.5 MOA, 1 MOA, .5 MOA
Accessories- Picatinny Rail
Quick switch firing mechanism- N/A
Scope/Sights- Picatinny Rail
Muzzle Velocity- 750 m/s, 780 m/s 820 m/s
Firing System- XM8 short stroke gas piston
Miscellaneous/electronic information- Essentially an Hk416 with a shortened 6 point stock and utilizing magpul magazines.
Basic Information
The weapon is essentially the body of an HK416 with a very similiar short stroke firing system found in the XM8, G36 and Ar-18, firing the 6.5mm grendel round. The weapon also sports a muzzle break and hydraulic recoil buffer, to help reduce recoil, and a polygonal cobalt chrome barrel. The weapon comes in four main variants, the carbine, standard, marksmen, and SAW variant. While the barrel lengths vary on some models, in general the carbine length barrel is 10 inches, the standard variant is 14.5 inches, and the sniperized and SAW variants each utilize 20 inch barrel.
The weapon uses a detachable polygonal cobalt chrome "flow formed" 5 groove 1:8.75 inch (1 complete turn in 1 in 8 inches / 222.5mm) right hand turn barrel; the barrel is made of an alloy that contains more than 50 percent cobalt. The barrel is roughly 13% heavier than standard steel barrels, but is more erosion and corrosion-resistant and is designed to retain high strength during long-term exposure to high temperatures. Cobalt alloys are frequently used in the aerospace industry, such as the hot-gas section of turbine engines. A proof of concept M240 7.62mm x 51mm NATO barrel, in practice, had 24,000 rounds test-fired through it, causing it to reach temperatures of 1,100 degrees, without failure. A steel barrel would have failed under such treatment.
The barrel itself, combined with polygonal barrel, in use with the Hk416 rifle is extremely durable, and has a minimum 20,000 round barrel life, although it is possible to extend this or get use out of the rifle after the minimum is reached. The barrels come in 10, 14.5, 16, and 20 inches.
The magazine capacity is approximately 30 rounds with a standard magazine, sporting 6.5mm grendel rounds. The magazine is based off of the magpul magazines, and similiar to the XM8's magazines, which are significantly more reliable than standard STANAG magazines. The ak-47 is capable of holding 30 18.5 gram rounds, or being reliable with approximately 550 grams, with the limitations largely due to the magazine shape and spring strength. The M16, theoretically, using 12.5 grams, could carry up to 45 rounds; however, even though this was the maximum reliability limit for the 5.56mm, it was still too unreliable to be adopted for wide spread use, especially compared to the Ak-47, and instead the 30 round magazine was adopted. Utilizing a better feeding method, with a slightly differently shaped round, and an inherently better magazine and feeding design, with a shorter magazine well, the reliability can be increased considerably. The XM8 magazine scored considerably higher than the M16 in terms of reliability. Thus, this increase in reliability allows the use of 30 6.5mm grendel rounds, instead of 26, and generally aids in reliability.
The firing system is based off of the Hk416, which a short stroke gas piston system, similiar to that in the AR-18, FN SCAR, or XM8. The firing similiar to the XM8, which has proven to be an extremely reliable weapon platform, with an extremely reliable firing system; it should be noted that the weapon and bolt has an extra seal on it, however, as the weapon is caseless (much like in the LSAT). The weapon was noted as being able to fire over 400 rounds from drum magazines without a single failure within 5 minutes. It is reported to be capable of firing 15,000 rounds without cleaning or lubrication, although the weapon is expected to be cleaned often. Moreover, 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. Even in extremely dusty and dirty environments, without cleaning the weapon is expected to fire be able to fire 472 rounds without any jams or stoppages. However, with the HK416, 117 of the 233 malfunctions were from just one of the 10 weapons. Over-all this gives the weapon comparable reliability to the XM8 (which it is based off of) and 8 times higher reliability than the M4 carbine or similar firearms, with a variety of operating conditions being less hazardous to the over-all functioning of the firearm, including sandy or wet conditions, which can directly impede the gases.
The weapon is made from composites and polymers similar to the P90 and XM8, to both reduce the cost and weight as of the weapon, as well increase the durability. The weapon fires from a closed bolt for both maximum accuracy and reliability.
Each barrel possess a muzzle break designed after the surefire muzzlebreak. The muzzle break can reduce the recoil of weapon by nearly 50%. In conjunction with the hydraulic recoil buffer, similiar to the M240 recoil buffer, the recoil is less than a quarter of what it would be without it. The muzzle break is incorporated into a large silencer, similiar to that of the Knights Armament SR-25 suppressor, which wraps over the barrel, in order to reduce the over-all length of the weapon; as a result of the suppressor, no additional flash suppressor is required. This not only reduces the noise of the weapon, enough to not require hearing protection, but also makes it difficult to hear the weapon at all past 200 yards, and reduces the recoil of the weapon, while not increasing the length of weapon considerably like with an ordinary suppressor.
As well, the design of the weapon and it's straight back recoil impulse, as well as the tighter, more steady grip on the weapon, combined with the impact gel recoil pad, makes the weapon very easy to use and relatively comfortable.
In addition, the weapon is designed to be used with the XM25 airburst firing scope and platform, enabling the weapon to have an "integrated" airburst function. While the electronic equipment is not integrated, it can be added with relatively little ease, and be used much in the same way that it was designed to be used on the XM29. This also allows for grenades to be fired easier, as the firing controls are next to the trigger and pistol grip for ease of reach.
The weapon uses a Blackbox round counter that can be hooked up to an LCD screen to show the rounds remaining. The magazines are generally color coded, which provides indication of how many rounds are within each magazine, although loading in another magazine that does not meet the criteria can result inaccurate round counting predictions; the round counter mechanism itself, however, will not falter.
The weapon uses an extendable stock in a similar manner to sniper stocks. Despite being a bull-pup, several multiple point guiding stocks are used to allow the user to adjust the pull of the stock up to three inches. While extendable, the stock adjustments must be made by loosening and tightening multiple facets, making extending or retracting the stock take a relatively large amount of time.
While picatinny rails are integrated into the weapon, many attachments are expected to be used with the weapon, regardless of the versatility of the system.
