HK

The MR556A1 is a direct descendant of the world-famous HK416. It offers the civilian semi-automatic shooter battlefield-proven reliability durability and precision you would expect from Heckler & Koch. - This latest update to the MR556A1 includes an updated grip and forearm as well as a lighter barrel profile that removes nearly a pound of front-end weight from the rifle. - The MR556A1 is assembled in the USA using US- and German-made components and uses many of the same parts and assemblies developed for the HK416. - Like the HK416 the MR556A1 uses a proprietary HK short- stroke gas piston in place of the direct-gas-impingement system found on lesser AR15-style rifles that propels exhaust gas into the upper receiver to operate the action. In the closed HK piston system exhaust gasses never enter the receiver which means the HK runs cooler cleaner. That is where that legendary HK reliability comes from. - When adverse conditions like dust sand and mud are introduced the advantage of the HK system becomes even more drastic. That is why so many of the world's military and law-enforcement elite customers trust HK. - The MR556A1's barrel is cold hammer forged from the highest quality cannon-grade steel with a slightly smaller diameter at the muzzle for improved accuracy and velocity. While the material and cold hammer forging process themselves greatly enhance durability HK's processes include many additional steps not taken by other manufacturers to produce superior accuracy and service life ensuring performance well beyond mil-spec - Caliber 5.56 x 45 mm NATO - Operating principle Gas operated short stroke piston - Bolt system Rotating bolt - Magazine 10/20/30 rounds - Mode of fire Semi-automatic - Length maximum (stock extended) 37 in / 940 mm - Length minimum (stock retracted) 33.75 in / 857 mm - Width 3.07 in / 78 mm - Height 9.45 in / 240 mm - Barrel length 16.5 in /421 mm - Weight Rifle (with empty magazine) 7.60 lb / 3.45 kg - Trigger pull 7.64 lb / 34 N ( approximate) - Barrel profile 6 lands & grooves right twist 1 in 7 in (178 mm) - Sights Optics ready - Adjustable buttstock Six positon adjustable MR buttstock