Wes/Tex said:
Don't know about original dates but these were in use thru the late 18th and early 19th century. Most surviving pieces are probably old pieces from the Royal Navy, though a few American pieces are known. The flintlock mechanism was used on all the lower gun decks on fighting ships where portfires and slowmatch would be too dangerous to use with all the powder around.
It was a real advantage to Nelson's fleet to have flintlocks on their guns because they could fire just as their guns came to bear. The enemy guns went off with less precise timing, meaning that when a ship is rolling, the shot may well go into the sea or through the sails, instead of striking timber and doing real damage. Watch a crew fire a cannon with slowmatch sometime: it will go off within 5-10 seconds of when the gun captain wants it to.
Read "Trafalgar: The Nelson Touch" by David Howarth and you'll have a grin on your face, and a tear in your eye.