Back boring is a process which is used to enlarge the bore diameter and correct non-concentricity of a shotgun barrel. This process reduces wall friction between the shot load and barrel thereby reducing recoil and shortening the shot string. Back boring also allows the shot load to be controlled by the choke tube rather than the barrel's bore constriction. This allows the shooter flexibility to switch choke constrictions as needed with confidence that the result will reflect that choice. Back boring will greatly reduce pellet deformation by allowing a more smooth path for the shot load through the shotgun's bore, and this will provide a more dense and even pattern.

Ballistic Specialties uses a line boring machine with a diamond hone running in an oil bath to produce an absolutely mirror smooth finish with true concentricity from forcing cone to muzzle After back boring a barrel any previous chokes will no longer be safe to use with the shotgun and must be replaced with tubes to match the new larger bore diameter.