Heckler and Koch built this tiny bottlenecked screamer in the late 1990s for the MP7 personal defense weapon as their answer to the 5.7. It is a slick little military round that barely exists in civilian life and mostly shows up as a curiosity in the rare guns chambered for it. Exotic and expensive and thoroughly Teutonic.
Loads run very light 30 to 40 grain bullets in a narrow specialty menu. Genuinely scarce and priced like the imported exotic it is. The tiny crowd with guns for it buys whenever anything surfaces.
