Shorter length provides extra rigidity and strength in tough materials.
Reamers are made to a plus tolerance.
Production length reamers have the same overall lengths as jobber length drills to facilitate ease of setup in automated drilling and reaming equipment. This includes the simple dual drilling and reaming cycle operations in small drill presses or bench lathes, as well as the high cycle automatic screw machine operations. These reamers have a median overall length between stub screw machine reamers and regular length chucking reamers.
CAUTION: Any cutting tool may break or shatter under improper use. Government regulations require use of safety glasses and other appropriate safety equipment at all times in the vicinity of use.