There are probably people that will read this that don't understand pin fire guns.
This is a photo of a pin fire bullet.
The hammer hits the protruding pin, which then is driven into and strikes the primer located inside the cartridge case.
This type of gun was invented by Frenchman Casimir Lefaucheux in 1828 but not patented until 1835. They were not popular in England or the United States, because the red neck gun makers of that day, pointed out how dangerous a gun that broke apart in the middle was, compared to the well made, solid muzzle loader. But I guess pin fire guns were used a lot in Europe, some even in the military, with the pistol being the most popular rather than shot guns or rifles. The pistols became popular for ease of loading as breech loaders in the days of muzzle loaders, but the pin fire was a much under powered cartridge, and by the civil war when more powerful revolvers were being developed, the pin fire guns began to loose their popularity. Kuger is probably right about the age being mid 1800's, however pin fire pistols were manufactured in France until about 1880. However, in the late 40's, I was probably 11 or 12, I bought a novelty pin fire pistol which couldn't have cost much money, because I didn't have much. It was supposed to shoot very small pin fire blanks, and the sucker was really loud. We found that about number 6 bird shot would fit in the barrel, and now the darn thing became dangerous, and yes, I got in trouble once again, but not for injuring anyone, it made a cute little hole in a window pane. Of course I lost the gun, and my butt was warmed, but I expect now days I'd have been rounded up as a terrorist, and probably do hard time, and never allowed to own a gun again.
