A simple shotgun at close range with the right load is a simple, but very effective defensive weapon.
Great story. These Muhammadan terorists should stick to riding camels and raiding camel caravans. Muhammad didn't leave any instructions on how to terrorize on the open sea.
The shotgun was effective because the pirates chose poor tactics and came into shotgun range too soon. It would have been useless beyond 100 yards. A good weapon to have, obviously, once the pirates came inside of its range.
the turks weren't very good at it either.