Percussion Cap Lock be a lock that used a percussion cap struck by the hammer to set off the main charge, rather than using a piece of flint to strike a steel frizzen. The caplock be easier to load, more resistant to weather, and was much more reliable than the flintlock. Many older flintlock weapons were later converted into caplocks so that they could take advantage of this increased reliability.
Used from 1820 to 1880 by most countries, so they would only be seen during the second half of the Late Pirate Era.
Many re-enactors use it because of the reliability and lower maintenance. It would be very embarrassing to perform a black powder demonstration fer a large crowd and not have the weapon fire, so convenience wins out on authenticity, since the general crowd of on lookers will not know or care about the difference. We carry percussion cap weapons because many of arrr customers asked for them.