View Full Version : Original Proof Gallons v. Liquid Gallons

12-16-2011, 16:09
Was looking at the tech sheets for the BTAC's and noticed the barrel size was listed in two different measurements: Original Proof Gallons & Liquid Gallons. What is the difference?

12-16-2011, 16:24
Liquid Gallons are a normal liquid measurement. If you pick up a gallon of milk at the store that is one Liquid Gallon. Nothing fancy.

Proof gallons are gallons based on 100 proof alcohol. That same gallon of milk, emptied, and refilled with 80 proof Vodka is .8 proof gallons. Fill it with 125 proof White Dog it becomes 1.25 Proof Gallons. I believe this was started solely for tax purposes. I know Distilleries pay taxes that way now, and I'm pretty sure I've heard Proof Gallons reference when talking about the Whiskey Rebellion.