Here is a patent manuscript by Casimir Lefaucheux. It is French patent number 8955 from 1850. It describes a reusable pinfire shotshell that has a base that unscrews to allow easy reloading. It also pictures a tool to extract the shell from the gun and unscrew it.
By 1850, pinfire shotshells had been on the market for 15 years and people were familiar with these new breech-loading guns. But they were still more expensive than buying a percussion cap and powder used by a muzzle-loading, percussion gun. Shotshells that were able to be reloaded was one solution to this issue. And many manufacturers made metallic shotshells that could be reloaded many times.