Pirate Weapons is Episode 4 of Season 2. It aired on July 23rd, 2003. Here's the synopsis from TV.com:
Actor and fight master Peter Woodward teaches the Conquest Team a brief history of pirates. The team learns about the weapons of 17th-century Caribbean pirates and various combat techniques with them, both offensive and defensive. Then the team members face off against the crew of a merchant vessel to find out if they have learned how to win with pirate weapons.