A reposable surgical instrument, comprising: a handle assembly including: a housing; a drive bar slidably supported within the housing; a trigger pivotably connected to the housing and operably coupled to the drive bar such that movement of the trigger relative to the housing from an un-actuated position to an actuated position translates the drive bar from a proximal position to a distal position; a ratchet pawl pivotably supported on the drive bar; and a receiver assembly extending from the housing and configured to releasably engage an endoscopic assembly (200,300,400,500,600,700) therein; and a first endoscopic assembly (200,400,500,600) configured for ratcheting use, the first endoscopic assembly including: a proximal hub (210,410,510,610) insertable into and releasably engagable within the receiver assembly, the proximal hub including a ratchet rack (215,415,515,615) disposed therein, the ratchet rack defining a plurality of ratchet teeth; an elongated shaft (220,420) extending distally from the proximal hub; an end effector assembly supported at a distal end of the elongated shaft; and a drive assembly (230,430) including an inner shaft slidably disposed within the proximal hub and the elongated shaft and defining proximal and distal ends, the distal end of the inner shaft operably coupled to the end effector assembly such that movement of the inner shaft from an un-fired position to a fired position effects manipulation of the end effector assembly, wherein, with the proximal hub releasably engaged within the receiver assembly, initial translation of the drive bar from the proximal position towards the distal position moves the ratchet pawl into engagement with the ratchet rack and the drive bar into abutment with the drive assembly such that further distal translation of the drive bar towards the distal position incrementally urges the inner shaft from the un-fired position towards the fired position as the ratchet pawl is incrementally advanced along the ratchet rack in successive engagement with the ratchet teeth thereof. a handle assembly including: a housing; a drive bar slidably supported within the housing; a trigger pivotably connected to the housing and operably coupled to the drive bar such that movement of the trigger relative to the housing from an un-actuated position to an actuated position translates the drive bar from a proximal position to a distal position; a ratchet pawl pivotably supported on the drive bar; and a receiver assembly extending from the housing and configured to releasably engage an endoscopic assembly (200,300,400,500,600,700) therein; and a housing; a drive bar slidably supported within the housing; a trigger pivotably connected to the housing and operably coupled to the drive bar such that movement of the trigger relative to the housing from an un-actuated position to an actuated position translates the drive bar from a proximal position to a distal position; a ratchet pawl pivotably supported on the drive bar; and a receiver assembly extending from the housing and configured to releasably engage an endoscopic assembly (200,300,400,500,600,700) therein; and a first endoscopic assembly (200,400,500,600) configured for ratcheting use, the first endoscopic assembly including: a proximal hub (210,410,510,610) insertable into and releasably engagable within the receiver assembly, the proximal hub including a ratchet rack (215,415,515,615) disposed therein, the ratchet rack defining a plurality of ratchet teeth; an elongated shaft (220,420) extending distally from the proximal hub; an end effector assembly supported at a distal end of the elongated shaft; and a drive assembly (230,430) including an inner shaft slidably disposed within the proximal hub and the elongated shaft and defining proximal and distal ends, the distal end of the inner shaft operably coupled to the end effector assembly such that movement of the inner shaft from an un-fired position to a fired position effects manipulation of the end effector assembly, a proximal hub (210,410,510,610) insertable into and releasably engagable within the receiver assembly, the proximal hub including a ratchet rack (215,415,515,615) disposed therein, the ratchet rack defining a plurality of ratchet teeth; an elongated shaft (220,420) extending distally from the proximal hub; an end effector assembly supported at a distal end of the elongated shaft; and a drive assembly (230,430) including an inner shaft slidably disposed within the proximal hub and the elongated shaft and defining proximal and distal ends, the distal end of the inner shaft operably coupled to the end effector assembly such that movement of the inner shaft from an un-fired position to a fired position effects manipulation of the end effector assembly, wherein, with the proximal hub releasably engaged within the receiver assembly, initial translation of the drive bar from the proximal position towards the distal position moves the ratchet pawl into engagement with the ratchet rack and the drive bar into abutment with the drive assembly such that further distal translation of the drive bar towards the distal position incrementally urges the inner shaft from the un-fired position towards the fired position as the ratchet pawl is incrementally advanced along the ratchet rack in successive engagement with the ratchet teeth thereof.