While named the 318, it uses bullets of .330 diameter and the case looks very much like the 30-06.  Introduced in 1910 by Westley Richards, it is sometimes referred to as the 318 Rimless Nitro Express or 318 Accelerated Express.  Well suited to a standard length action, only the odd bullet diameter makes it difficult to load for.  It is priced per 20 cases and the shipping weight is 255 g/20.