A half barrel is equivalent to a keg, which has a capacity of 15.5 U.S. gallons of beer, equivalent to 124 U.S. pints. Read more: How Many Beers Come in a Keg? | eHow.com http://www.ehow.com/facts_4969963_how-many-beers-come-keg.html#ixzz1IfjEEovj