Russia’s Gepard PDW looks to be a real comer in the PDW arena. The gun apparently allows the operator to fire different types of 9mm rounds with different
lengths without changing the magazine or barrel. It also utilizes some kind of "anti-recoil system". One of the rounds it can fire is the 9x30mm Grom round, which has special armor piercing capabilities.
To read more about it and see pictures, CLICK HERE.