The puncheon was a British unit for beer, wines and spirits.[1] It was also an American unit of capacity for wine.[2]
Historically, the puncheon has been defined somewhere between 70 and 120 imperial gallons (318 and 546 litres; 84.1 and 144 US gallons).[1]
The US puncheon for wine is defined as 84 US gallons (318 litres).[2]