A biopsy device , comprising: a hydraulic drive assembly that includes: a chamber housing configured to define a proximal chamber , distal chamber , and a transition chamber , the transition chamber being interposed between the proximal chamber and the distal chamber, wherein the proximal chamber, the transition chamber, and the distal chamber collectively form a continuous passage in the chamber housing; a drive piston located in the proximal chamber and configured to move in the proximal chamber; a driven piston located in the distal chamber and configured to move in the distal chamber; a cavity defined in the chamber housing between the drive piston and the driven piston; and a hydraulic fluid of a fixed quantity that fills the cavity between the drive piston and the driven piston to establish a hydraulic connection between the drive piston and the driven piston; a drive mechanism drivably connected to the drive piston, the drive mechanism configured to move the drive piston in the proximal cylinder; and an elongate biopsy member is connected to the driven piston, characterized in that the proximal chamber has a first transverse area and the distal chamber has second transverse area, the first transverse area being larger than the second transverse area. a hydraulic drive assembly that includes: a chamber housing configured to define a proximal chamber , distal chamber , and a transition chamber , the transition chamber being interposed between the proximal chamber and the distal chamber, wherein the proximal chamber, the transition chamber, and the distal chamber collectively form a continuous passage in the chamber housing; a drive piston located in the proximal chamber and configured to move in the proximal chamber; a driven piston located in the distal chamber and configured to move in the distal chamber; a cavity defined in the chamber housing between the drive piston and the driven piston; and a hydraulic fluid of a fixed quantity that fills the cavity between the drive piston and the driven piston to establish a hydraulic connection between the drive piston and the driven piston; a chamber housing configured to define a proximal chamber , distal chamber , and a transition chamber , the transition chamber being interposed between the proximal chamber and the distal chamber, wherein the proximal chamber, the transition chamber, and the distal chamber collectively form a continuous passage in the chamber housing; a drive piston located in the proximal chamber and configured to move in the proximal chamber; a driven piston located in the distal chamber and configured to move in the distal chamber; a cavity defined in the chamber housing between the drive piston and the driven piston; and a hydraulic fluid of a fixed quantity that fills the cavity between the drive piston and the driven piston to establish a hydraulic connection between the drive piston and the driven piston; a drive mechanism drivably connected to the drive piston, the drive mechanism configured to move the drive piston in the proximal cylinder; and an elongate biopsy member is connected to the driven piston, characterized in that the proximal chamber has a first transverse area and the distal chamber has second transverse area, the first transverse area being larger than the second transverse area. <EOS>