Berdan

Berdan refers to a type of firearm and ammunition developed in the United States during the American Civil War. The Berdan rifle was a single-shot, breech-loading rifle that utilized a distinctive primer design. It was named after its inventor, Hiram Berdan, a colonel in the Union Army. While Berdan was the primary designer and proponent, the rifles were manufactured by several different companies, including Colt and Sharps.

The key innovation of the Berdan system was its primer. Unlike the rimfire primers common at the time, Berdan primers were a central-fire type. This meant a small anvil was integrated into the primer pocket itself, and the primer contained a small percussion cap that would be struck by the firing pin, igniting the main propellant charge. This design was considered more reliable and powerful than many contemporary rimfire systems.

Berdan cartridges were also unique. They featured a hollow base, and when fired, the expanding gases from the propellant would press outwards against this hollow base, creating a tighter seal in the breech and improving the rifle's performance. The Berdan system was adopted by the Union Army and saw significant use during the Civil War. After the war, the design, particularly the central-fire primer concept, influenced future ammunition development. Although the Berdan rifle itself was eventually superseded by more advanced repeating firearms, its contribution to firearm technology, especially in the realm of ammunition, was noteworthy.