The .30 caliber "big brother" to the combat-proven 5.56 mm HK416 family of rifles and carbines, the HK417 shares the operating control location and functions, disassembly and maintenance procedures, and ergonomics of the HK416 and other AR15-based weapons, including the US M16 and M4-type rifles and carbines. This fact insures immediate operator acceptance and transfer from one weapon to another and retains the already learned muscle memory critical to proficient target engagements when under stress.
The HK417 uses the unique operating rod gas system pioneered by HK in the HK416 and G36 weapons systems. This system uses a solid "pusher rod" operating rod in place of the more common hollow gas tube normally employed in AR15-style rifles.
This system improves reliability and reduces operator cleaning and maintenance as no carbon fouling or propellant gases are directed back into the weapon beyond the gas piston located above the barrel. The cleaning intervals and heat transfer to bolt components are drastically reduced, while the service life of all parts as well as the barrel, is increased dramatically.
The design goal of the HK417 is to ensure no parts failures or stoppages in less than 10,000-15,000 rounds with little or no accuracy degradation. The HK417 gas system also makes the weapon less sensitive to ammunition and barrel length changes, or when sound suppressors are employed.
The HK417 will be available with 12, 16, and 20-inch (305, 406, 508 mm) barrels. Barrels can be easily changed in less than two minutes with simple tools. HK417 barrels are manufactured using HKâ€™s proprietary cold hammer forging process, are chrome-lined, and use a conventional lands-and-grooves bore profile with a 1 in 11 inch twist. All HK417 barrels are threaded for flash hiders, muzzle compensators, and for sound suppressor attachment.
An HK-designed multi-position retractable buttstock provides a comfortable sloping cheek piece, multiple battery storage compartments, and enhanced non-slip rubber recoil pad. Ambidextrous operating controls are standard on the HK417, including the charging handle and an ambidextrous safety/selector lever is also planned.
Semiautomatic and fully-automatic modes of fire are available as a standard feature. A semiautomatic only option is also projected. All manner of existing accessories, including sights, laser aimers, pistol grips, slings, etc. can be fitted to the common attachment points and/or MIL STD 1913 rail system (HK Free Floating Rail System) found on the HK417.
During HK-conducted desert testing, a single HK417 prototype (2nd design stage) fired more than 15,000 documented rounds of assorted ammunition, to include M118LR, M80 ball, M993 AP and assorted commercial ammunition with bullet weights ranges from 125 to over 175 grains without a single parts failure or stoppage!
Accuracy firing with a prototype 12-inch barreled HK417 carbine and 10X optical sight was conducted with user representatives using US M118LR ammunition. Firing multiple 3-shot groups at 100 - 500 yards lines, the average group size for all four shooters was 1.3 MOA from an HK417 carbine with 12-inch barrel!
The HK designed and patented, user removable, 4-quadrant free floating rail system for the HK417 mirrors that of the HK416 carbine and also accepts quick-detachable 40 mm HK grenade launchers.
Modular user installed mounting adapters allow the same grenade launcher to be used on existing and newly emerging weapon systems, including M16 rifles and M4 carbines. The HK free-floating rail system is removed without special tools by the operator and insures 100% return to zero for all mounted accessories.