This sour mash, small batch whiskey is made from 70% corn, 21% rye and 9% malted barley. It's distilled in copper stills then matured in hand-selected, 53-gallon, charred American oak barrels for between two and four years. We use a #4 char. Like all of our small batch whiskeys, Wheel Horse Bourbon is bottled at 101 proof and without chill filtration.