HK 4.6×30mm
The HK 4.6×30mm (designated as the 4,6 × 30 by the C.I.P., and 4.6×30mm NATO) cartridge is a small-caliber, high-velocity, smokeless powder, rebated, bottleneck, centerfire cartridge designed for personal defense weapons (PDW) developed by German armament manufacturer Heckler & Koch (HK) in 1999. It was designed primarily for the MP7 PDW to minimize weight and recoil while increasing body armor penetration.