A 8 gallon still fill will get you a couple gallons of alcohol. Probably a gallon of drinkable spirit. If you double distill, cut that back to 3 quarts of finished product to put in the barrel. It takes a lot of work (or a big still) to make 10 gallons of finished product. The more you distill, the higher the proof but the less you get. Higher proof needs to be proofed down for finishing though.
