In this video by PlaSSo, he shows an airsoft rifle that takes some of the best bits from FN Herstal --- an FN SCAR rifle that uses an 5.7mm magazine in the form of the P90-style AEG magazine. This is a custom job so don't expect it to be mass produced for the airsoft market... "I wanted to make an AR-type toy gun that uses a P90 magazine like AR57 and FSS Hurricane."