In 1867, the British War Office adopted the Eley-Boxer metallic centerfire cartridge case in the Enfield Pattern 1853 rifles. These were converted to Snider-Enfield breechloaders based on Jacob Snider’s design. In America, Springfield Model 1861 muzzleloaders were converted to breechloaders based on Erskine Allin’s design, creating the Model 1865. There have been improvements in metallurgy, cartridge and firearm design, but general-issue rifles and machine guns have been using metallic cartridges ever since.
Metallic cases contain, protect and hold the components in proper place during carry, chambering and firing. They help seal the chamber during firing. They then act as a heat sink, removing some heat from the chamber during ejection. The downside is the container often weighs about as much as the active components it contains. But attempts to do away with the cartridge case in self-loading small arms have yet to make …Read the Rest
Source:: Tactical Life