The original design of the VBR-Belgium PDW/CQBW dates from a few years ago. At that time an answer was seek to withstand in combat against an entry of a hostile assault team. Therefore a new Close Quarter Battle Weapon (CQBW) was developed in a special VBR 6 mm CQBW caliber. Although this special VBR 6 mm CQBW caliber had special identities ideal for this weapon, it is very difficult and expensive to bring a new caliber on the market. The VBR-CQBW could also be used in an experimental 5.7x28 mm Short caliber. However the only caliber which is on an industrial scale on the market with identities very close to these of the original VBR 6 mm CQBW is the current 4.6x30mm caliber.