Jack Daniel’s Single Barrel Rye is the first time the Jack Daniel’s distillery has used a mashbill other than their traditional 80% corn, 12% barley and 8% rye since 1866. To make this rye the good folks at Jack Daniel’s didn’t just eek in across the line at 51% rye like some brands tend to do. No sir, they came barreling across the line at a whopping 70% rye to really dig into that lovely rye character.