This item is a small powder keg used in the 2003 Russell Crowe sea epic Master and Commander: The Far Side of the World.

Items such as this can be seen throughout the film as Capt. Jack Aubrey (Crowe) leads his crew on the hunt for a French Privateer during the Napoleonic Wars. The keg is made of wood and has been painted dark red. On the top is a lift-off lid which is connected to the keg itself by thin rope which also acts as a carry handle.

Inside the long and hollow cylindrical piece is where the powder was actually stored.

COA: Prop Store of London

A scene in the movie where the Powder Kegs can be clearly seen...