The puncheon was a British unit for beer, wines and spirits. It was also an American unit of capacity for wine.
Definition
Historically, the puncheon has been defined somewhere between .
US unit of capacity for wine The US puncheon for wine is defined as .
Conversion
1 puncheon = 70-120 gallons 1 puncheon = 0.318-0.546 m3 or 318 to 546 litres.
US unit of capacity for wine
1 puncheon = 4/3 Hogshead 1 puncheon = 84 gallons 1 puncheon = 0.317974589856 m3 or about 318 litres.
See also English wine cask units
References