- 01: Introduction
- 02: History
- 03: Propellants, Firearms, and Ammunition Development
- 04: Modern Firearms Manufacture
- 05: Small Arms Ammunition
- 06: Evidence Handling Procedures
- 07: Equipment and Instrumentation
- 08: Examination of Firearms
- 09: Cartridge and Shotshell Examination
- 10: Characterization and Evaluation of Fired Projectiles
- 11: Bullet Comparison and Identification
- 12: Gunshot Residue and Distance Determination
- 13: Toolmark Identification
- 14: Communicating Results
- Resources
Modern Developments
Home > Propellants, Firearms, and Ammunition Development > Ammunition > Cartridge Cases > Modern Developments
Today, variation in cartridge case construction is seen only in the primer pocket. An English development, Boxer priming, placed the anvil in the primer as a separate part. The primer pocket has a single, large flash hole on the case centerline. The American development, Berdan priming, makes the anvil an integral part of the case and has one to three small flash holes positioned around the anvil.
Boxer primed case with
flash or vent hole
For most purposes, the type of priming system is transparent to the end user. However, Boxer priming has an advantage to those who prefer to recycle the case by reloading. The centrally placed flash hole in the Boxer system allows the spent primer to be removed with a thin punch tool and a new primer inserted. Ironically, most of the world adopted the American Berdan system while America adopted the English Boxer system.
Berdan primed brass case
Over the years, cartridge cases have been manufactured using a variety of materials. Although aluminum has been growing in popularity, brass, specifically cartridge brass, (70 percent copper/30 percent zinc) is most common in Western European and American sporting ammunition. Mild steel (steel with low carbon content) has been used where iron is a more abundant resource than copper. Both steel and brass have similar abilities to withstand pressure.
Ammunition for modern shotguns uses a hybrid cartridge case with the following features:
- Body made of paper or flexible plastic
- A plastic or composition base wad around the primer
- A thin metal base section that provides adequate grip for the extractor and support for the primer
In the past, all-brass shotshells were used and are still seen today in some sports; the hybrid case represents the majority of shotshells produced and fired.
