Patent 9528799 was granted and assigned to Mac (rapper) on December, 2016 by the United States Patent and Trademark Office.
Ammunition casings that have optimal external cartridge dimensions for polymeric cases are provided. Polymeric ammunition cartridges and casings are presented having a neck portion of the polymeric case dimensioned for optimal fit within a firearm chamber. The polymeric ammunition casing may include one or both of an extended neck region and an internal cannelure engaging portion.