H&K G11.

The Heckler & Koch G11 is a non-production prototype assault rifle developed during by Heckler & Koch (mechanical engineering and weapon design), Dynamit Nobel (propellant composition and projectile design), and Hensoldt Wetzlar (target identification and optic systems). In 1990, H&K finished the development of the G11, intended for the Bundeswehr and other NATO partners. Although the weapon was a technical success, it never entered full production due to the political changes of German reunification and lack of procurement contract. Only 1000 units were ever produced, some of which made their way into the hands of the Bundeswehr. The rifle is noted for its use of caseless ammunition in calibers 4.73 × 33mm, 4.92 x 34mm and 4.73 × 25mm with the propellant shaped into cuboid blocks. The projectile is 4.93 mm in diameter with a case length of 33 mm, the US case length measurement is 34 mm since for the ACR trials the chamber length, not the actual case length was used. The 4.73 mm round is half the weight and 40% the size by volume of the 5.56×45mm NATO round. The round was designed to the same ballistics requirement as the 5.56×45mm NATO round but the 4.73mm is much less likely to tumble when hitting or penetrating a soft target, and thus not as lethal. The weapon itself has three firing modes: semi-auto, full-auto at 460 rounds per minute, and three-round burst at over 2100 cyclic rounds per minute, or approximately 36 rounds per second. The loading and feed mechanism is physically very complicated but exceptionally fast and reliable.