If you've lucky enough to have acquired an empty whiskey barrel from a local distillery, take heart; with a little patience and care, there is still plenty of fine whiskey in the barrel just waiting for you to extract it!
Remove the bung from the barrel. A pair of needle nose pliers should do the trick. Just grip the lip of the bung with your pliers and slowly pull up. Rotate your pliers all around the circumference of the bung until it releases from the barrel.
Inspect the bung for quality. If it's damaged or cannot create a tight seal, you will need a new bung to replace it. Contact your local beer and wine shop for a replacement.
Inspect both inside and outside of the barrel. If there are any cracks or holes in the barrel, then it is not suitable for sweating. Also make sure the inside is free of dust, bugs, or cobwebs as these will seriously affect the quality of the final product.
Pour 2 gallons of distilled water into the barrel.
Recap the barrel with the bung. With a rubber mallet, hammer down the bung to form an airtight seal.
Find a place outdoors to store your barrel. It's important that the barrel gets as much sunshine during this phase as possible. If the forecast calls for rain, be sure to move the barrel into a dry, weather safe place.
Roll your barrel around every day. Lay the barrel on its side. On a clean flat surface, roll the barrel back and fourth for several minutes. You want to get every part of your barrel saturated to ensure a maximum yield of whiskey.
Reopen the barrel after seven to ten days for inspection. At this point, you should be producing a very weak whiskey. Be sure to look out for insects in the brew, possible mold, or any odd smells. If so, the batch may be contaminated. Do not consume if any of these signs are present. Reinsert the bung if the batch is good.
Continue to roll the barrel daily.
Transfer the whiskey to storage jars. After three to four weeks, the resulting whiskey should be ready to drain. Remove the bung and drain out the product through a fine mesh screen into a sterilized jar for storage.
Let your whiskey age. Store the jars of whiskey in a cool dark area for a minimum of 3 months. The resulting matured whiskey should contain anywhere from 35 to 40 percent alcohol.