An older system where 100 proof was roughly 57.1% ABV. This is largely obsolete but still referenced in "Gunpowder Proof" labels. Does Age Affect Alcohol Content?
When a distillery takes a fantastic 10-year-old cask at 58% ABV and dilutes it to 40% ABV to sell more bottles, they are adding roughly 45% extra water to that barrel. That doesn't ruin the whisky, but it undeniably makes it thinner and less complex than the liquid that was in the cask. alcohol content of whisky
You will often see two different numbers on a bottle, especially in the United States. An older system where 100 proof was roughly 57
At these percentages, the whisky is diluted with water before bottling to ensure consistency and to make the spirit more "approachable" for the average palate. Understanding "Cask Strength" Whisky When a distillery takes a fantastic 10-year-old cask