Cannon can be purchased from the US or built from plans. CO2 tanks are either 20 oz, 7oz or 3.5 oz and are refillable and must have a syphon-type valve. The hobby is legal in Australia, being classified as an Adult Toy and not subject to any Firearms Act, with some States including Warship Combat in the exemptions to their Acts. All AusBG safety requirements, including the compulsory use of Safety Glasses, must still be followed. These define main and secondary armaments for the Battleships, Battlecruisers, Heavy and Light Cruisers and Destroyers.
Carriers are just large targets and submarines too small although work is being done on torpedoes.
Ships must close to 3m or 10 feet for BB's to penetrate the balsa skins and cause damage and sinkings. Floats are deployed by sunken ships and help recovery. Cargo ships are unarmed and slow but do have pumps and extra large rudders to help survive surface attack, and shore installations could have oil tanks, harbour facilities and defence batteries which could be attacked for additional points. No elevation of guns is permitted for safety reasons.