Here is an exceedingly rare example of a Civil War dated patented cartridge. This is the actual patent example and is engraved with the manufacturers name and town of New Haven, Connecticut. According to Frank Sellers book on Sharps Firearms, there were on two trials in regards to metallic cartridges between 1861 and 1862. Trial No. 1 examined .56 metallic cartridges and trial No. 2 examined the Kellogg conversions. This example could have been adapted to use in a number of breech-loaders if it were accepted by the Ordnance Department. While the cartridge was self-contained, it was still an externally primed cartridge. When the breech block was raised, it would cut off the raised nipple on the back of the cartridge exposing the powder. You would then place a percussion cap over the nipple and fire the rifle/carbine.