The 9×30mm Grom (Гром., Russian for Thunder) is a Russian round developed between 1992 and 1993, designed for the Gepard (submachine gun), it answers the need to defeat 1B2 body armor at a range of 100 meters.^[2][1]

A regular and an armor piercing variant were designed, the non-armor piercing bullet taken from the 9×19mm Parabellum and the armor piercing bullet was taken from the RG054 cartridge, it has a black painted tip.^[1]

The case is a cutdown 5.45×39mm (also blankfiring) round, manufactured from phosphate varnished steel. The propellants used are pyroxylin (standard Soviet pistol powder "П-45","П-125" also used for blankfiring 5.45×39mm and 7.62×39mm) or smokeless powder consisting of spherical ellipsoids which measure from 0.45–0.75mm, resulting in powder density of 0.95g/cm³.^[1]

• 9×23mm Winchester
• 9×25mm Mauser
• 9mm Winchester Magnum
• 9×25mm Dillon – shorter but wider 9mm bottlenecked cartridge with the same capacity
• .357 Magnum – similar rimmed cartridge