Convert from shot to drum [metric, petroleum]

Unit Definition (shot)
The shot is a traditional unit of liquid volume. The term "shot" is often used informally to mean "a small serving." In the U.S. a shot is legally equal to one fluid ounce or 29.574 milliliters. However, many bartenders use larger shot glasses holding 1.25 fluid ounces (37.0 milliliters), and some shot glasses hold the same as a jigger: 1.5 fluid ounces or 44.4 milliliters.

Unit Definition (drum [metric, petroleum])
The drum [metric, petroleum] is a unit of volume sometimes used in the oil trade. In the metric world, drums of 200 liters, 205 liters, and 208 liters are in use as substitutes for the traditional size.