This was a development by Bryan Collison during the early to mid-2000’s to provide improved extraction in the Encore pistol over the .50 AE, using readily available components. The case is based on the .500 S&W Magnum trimmed to a maximum of 1.285″. The same loading data as the standard 50 AE is used, with the 500 S&W Magnum shell holder. The standard .50 AE chamber is counter-bored to provide seating space for the rim.