What is the diameter of a jumbo drill? Jumbo drills, typically used in mining, tunneling, or other large-scale construction applications, have drill bits with diameters ranging from 25 mm to over 150 mm (1 inches to 6 inches).

　　Some specialized jumbo drills can support even larger bits for tasks requiring more extensive boreholes.

　　For instance, jumbo core bits used for drilling rock could have diameters ranging anywhere from 6 inches (152 mm) up to over 10 inches (254 mm).