Intellectual property and sales are growing for injection molded ammunition.
While the original goals of the technology were to reduce use of copper and other
expensive metals, other benefits are starting to win over an army of skeptical sportsmen. One is the lighter weight of the plastic composite cartridge, which translates into less wear and tear on guns as well as flatter—and more accurate—trajectory, according to manufacturers and patents, which exceed 100. Lead replacement is also an important benefit of the new ammunition.
Conventional ammunition for large caliber weapons is made from machined brass or lead that is machined, cast, molded or coated.
At least three companies are now injection molding ammunition: PCP Ammunition of Vero Beach, Florida; Polycase of Savannah, Georgia; and True Velocity, which is opening a new manufacturing plant in Garland, Texas.
A patent application published last Thursday by True Velocity shows the nature of the technology.
The polymeric cartridge casing could be made of a glass-reinforced polyamide, although several other plastics are mentioned in the patent application. Top and bottom halves would be welded together, a common practice in plastic processing. Injection molding would permit faster mass production with easier implementation of design features such as multiple cannelures that would improve effectiveness of the projectile. The projectile is injection molded with metals or ceramic alloys and can also include complex design features.
Polycase, which began making molded ammunition in 2012, operates two 80-ton Sumitomo Demag injection molding machines. It partnered with PolyOne to develop a special high-density compound for lead-replacement.