Percussion Cap with V-Shaped Anvil Explained

A percussion cap, often referred to as a primer, is a small, sensitive explosive device used in firearms. Its primary function is to initiate the firing sequence of a cartridge. When the firearm's firing pin strikes the primer, the explosive inside detonates, creating a small flame that travels through a small hole (flash hole) to ignite the main gunpowder charge within the cartridge case.

The anvil is a critical component within the primer assembly. It sits at the base of the primer cup and provides a hard surface against which the priming compound is crushed when struck by the firing pin, ensuring a reliable ignition.

Analyzing Primer Types and Anvil Shapes

The question asks to identify the type of percussion cap that features a 'V' shaped anvil.

Boxer Primer Anvil:

The **Boxer primer** is characterized by having a distinct, separate anvil piece seated in the primer pocket of the cartridge case. This anvil is often stamped from sheet metal and commonly takes a 'V' shape. This specific shape is designed to help direct the flame efficiently from the point of impact towards the flash hole and into the main propellant charge. The Boxer primer is also designed for easier removal and reloading, as the anvil is part of the primer itself, not the case.

Berdan Primer Anvil:

In contrast, the **Berdan primer** design integrates the anvil directly into the cartridge case head. The primer pocket in the case is formed with one or more small integral posts or raised sections that act as the anvil. The flame from the priming compound is directed through small holes in the primer cup to ignite the powder. Berdan primers are generally more difficult to remove and reload compared to Boxer primers.

Other Options Considered:

• Belted: This term typically describes a specific type of cartridge rim, like those found on "belted magnum" rifle cartridges. It does not refer to a primer anvil shape.
• Blank: A blank cartridge is designed to produce sound and flash without firing a projectile. While it uses a primer, the term "blank" refers to the type of cartridge, not the specific design of its anvil.

Conclusion on V-Shaped Anvil

Given the description of a 'V' shaped anvil, the percussion cap design that matches this feature is the **Boxer** primer.