This gun revolutionized assault weapon design. The weapon fires a caseless cartridge consisting of a block of propellant with a bullet buried inside. The resultant weight and space savings allow this weapon to have a very high magazine capacity.
Using 4.7mm caseless ammo, the H&K G11 is a weapon found in the mid-latter parts of Fallout 2. Although this gun is powerful, it is not as powerful as the H&K P90c submachine gun during burst firing, because this rifle fires only five shots per burst. The H&K G11E is a much superior version, capable of doing more damage per bullet, having longer range and firing seven rounds per burst.
Although outclassed by some other weapons, the G11 can be a capable weapon if/when enough ammo is available. Two bursts can tear apart wanamingos and even deathclaws, while also being very efficient with the rounds that go flying.
Although the G11 is an assault rifle, it uses the SMG animation when firing. This means that Sulik and Lenny can use this weapon, while Cassidy and Vic cannot.