The HK416 (5.56 mm) was developed by Heckler & Koch for U.S. special operations forces as a major product improvement of M4/M16-type carbines and rifles. Using the HK-proprietary gas piston system found on the G36, the HK416 does not introduce propellant gases and carbon fouling back into the weapon’s interior, making it the most reliable of any M4/M16 type weapon.
The HK416 has been combat-proven in Southwest Asia and has also gained the attention of military, law enforcement, and security users outside of the US. In April 2007, the HK416 was selected as the new Norwegian Army rifle.
The origins of the HK416 began with the realization of the deficiencies of the direct gas impingement (gas tube) operating system found on conventional M4/M16-style weapons. Input from the users of current M4/M16-type arms, high-speed video assessment, and extensive live-fire testing in extreme operational environments such as the U.S. Army Desert Proving Ground in Yuma, Arizona revealed multiple areas for improvement.
Improvements were made to the internal operating system and miscellaneous component parts to improve reliability in best and worse case scenarios, with all types of ammunition, with all barrel lengths and with and without sound suppressors attached.
An innovative free-floating 4-quadrant rail system designed by HK allows all current accessories, sights, lights, and aimers used on M4/M16-type weapons to be fitted to the HK416. This HK rail system and can be installed and removed without tools.
The HK-proprietary gas system uses a piston driving an operating rod to control the function of the bolt, preventing propellant gases and the associated carbon fouling from entering the weapon’s interior. This increases the reliability of the weapon and extends the interval between stoppages. It also reduces operator cleaning time, heat transfer to the bolt and bolt carrier, and wear and tear on critical components.
To improve reliability, service life, and operator safety during obstructed bore occurrences or after extreme extended firing sessions, the HK416 uses barrels produced by Heckler & Koch’s famous cold hammer forging process.
The highest quality steel is used in this unique manufacturing process producing a barrel that provides superior accuracy for greater than 20,000 rounds with minimal degradation of accuracy and muzzle velocity. HK416 variants are available with 10.4, 14.5, 16.5, and 20 inch (264, 368, 419, 508 mm) barrels. Some HK416 variants also have “OTB” (Over-the-beach) capability and can be safely fired after being submerged in water and not completely drained.
In addition to the improvements in the baseline weapon, HK has produced a corrosion resistant steel magazine and a proprietary buffer to improve functional reliability.
An add-on single shot 40 x 46mm grenade launcher module can be quickly attached to the rail system of all models without tools. HK has applied its proven and fielded Safety Blank Firing Attachment and Live Round Excluder Magazine technology to the HK416, eliminating the possibility of live rounds being loaded into and fired through a standard issue weapon outfitted for blank firing only.
The HK416 is available as complete carbine or rifle or as a “drop-in” HK416 upper receiver module for use on the lower receivers of existing M4/M16 type weapons.