Like its 5.56 mm counterpart, the MR762A1 is a semi-automatic rifle configuration with match rifle capability developed for civilian users. The MR762A1 uses the HK proprietary gas piston operating system, employing a piston and a solid operating "pusher" rod which virtually eliminates malfunctions common to direct impingement gas systems since hot carbon fouling and waste gases do not enter the receiver area. The HK Modular Rail System (MRS) is truly free-floating for maximum accuracy. The MRS handguard has a more ergonomic design, yet retains many features from the previous FFRS. It uses an HK proprietary keyhole design to allow the attachment of Picatinny rail segments to the handguard. The MR762A1 also has a Picatinny rail machined into the top of its upper receiver for mounting optics and mechanical sights. The MR762A1 is produced in the USA from both American and German-made components. The German-made barrel is produced by HK's famous cold hammer forging process with the highest quality steel for a barrel that provides superior accuracy and long service life. Ambidextrous operating controls are standard on the MR762A1, including a convertible charging handle and an ambidextrous selector lever. The MR762A1 uses the same 10- and 20-round translucent polymer box magazines made for the HK417. This model is supplied with one 20-round magazine and Troy Microsights.