The present invention is directed to an innovative, economical method or system disclosing a captive volume in a hydraulic circuit which can be selectively hydraulically or pneumatically locked, or vented in order to correspondingly maintain, or increase the total volume of the hydraulic circuit. The structural elements of an embodiment of the present invention may include an accumulator with or without a fixed solid stop, which limits its travel. The accumulator can either be a separate entity, or as an assembly within the master or slave pistons.