Federal Standards for Identity require that the limit on true US Boubon not exceed 80 Proof.
The following definition comes straight from those standards:
(1)(i) “Bourbon whisky”, “rye whisky”, “wheat whisky”, “malt whisky”, or “rye malt whisky” is whisky produced at not exceeding 160° proof from a fermented mash of not less than 51 percent corn, rye, wheat, malted barley, or malted rye grain, respectively, and stored at not more than 125° proof in charred new oak containers; and also includes mixtures of such whiskies of the same type.
I guess I should add that, yes, yes, I know Jack is “Tennessee Whiskey” and not technically a Kentucky “Bourbon” but there are lots of states where Bourbon is made and Tenn Whiskey is only made in Tennessee -— I know you guys in those two states are very sensitive about all these distictions.
Believe 80 proof (40% by volume) is the minimum for bottling. Distilled to 160 proof and into the barrel no more than 125 proof.
Cheers!
KYPD
Proof your whiskey with gunpowder!