The .510 DTC EUROP uses the same bullet as the .50 BMG, but has slightly different case dimensions. The case is 0.1 inches (2.54 millimeters) shorter and uses a steeper shoulder than standard .50 BMG ammunition. .510 DTC EUROP cases can be made by shortening and then fire-forming .50 BMG cases. The new round has almost identical ballistics, but because of the different dimensions, rifles chambered for the .50 BMG cannot safely fire the .510 DTC EUROP, and vice versa, and therefore do not fall under the same legal prohibitions. .510 DTC EUROP rifles, like .50 BMG rifles outside California, are simply standard modern rifles and can be purchased as such.