Barrels (UK) to gallons (US liquid) conversion calculator above calculates how many gallons (US liquid) are in 'X' barrels (UK) (where 'X' is the number of barrels (UK) to convert to gallons (US liquid)). In order to convert a value from barrels (UK) to gallons (US liquid) (from bl to gal) simply type the number of bl to be converted to gal and then click on the 'convert' button.