A biopsy device, comprising: a housing defining an interior chamber having a central axis; a sub-frame positioned in the interior chamber of the housing, the sub-frame having a separator wall and a proximal end wall, the sub-frame configured to define a distal interior chamber and a proximal interior chamber which are divided by the separator wall, the separator wall having a first lock opening and the proximal end wall having a second lock opening; a cutting cannula mechanism (16, 44) having a cutting cannula, a cutting cannula slider, and a cutting cannula spring, the cutting cannula slider being fixed to a proximal end of the cutting cannula, the cutting cannula slider having a first locking tang configured to selectively engage the first lock opening of the separator wall, the cutting cannula spring being interposed between the cutting cannula slider and the separator wall; a stylet mechanism having an inner stylet slidably received within a lumen of the cutting cannula, and having an inner stylet slider fixed to a proximal end of the inner stylet, the inner stylet slider having a second locking tang configured to selectively engage the second lock opening of the proximal end wall, an inner stylet spring being interposed between the inner stylet slider and the proximal end wall; and a cocking mechanism; characterised in that the sub-frame has a first rack gear and the cocking mechanism includes a cocking slider, a pawl, and a rotary gear, the cocking slider having a second rack gear, the rotary gear being interposed between the first rack gear of the sub-frame and the second rack gear of the cocking slider, the pawl having a proximal end, a distal end and a mid-portion between the proximal end and the distal end, the mid-portion of the pawl being configured to rotatably mount the rotary gear, the pawl configured to interact with each of the cutting cannula slider and the inner stylet slider. a housing defining an interior chamber having a central axis; a sub-frame positioned in the interior chamber of the housing, the sub-frame having a separator wall and a proximal end wall, the sub-frame configured to define a distal interior chamber and a proximal interior chamber which are divided by the separator wall, the separator wall having a first lock opening and the proximal end wall having a second lock opening; a cutting cannula mechanism (16, 44) having a cutting cannula, a cutting cannula slider, and a cutting cannula spring, the cutting cannula slider being fixed to a proximal end of the cutting cannula, the cutting cannula slider having a first locking tang configured to selectively engage the first lock opening of the separator wall, the cutting cannula spring being interposed between the cutting cannula slider and the separator wall; a stylet mechanism having an inner stylet slidably received within a lumen of the cutting cannula, and having an inner stylet slider fixed to a proximal end of the inner stylet, the inner stylet slider having a second locking tang configured to selectively engage the second lock opening of the proximal end wall, an inner stylet spring being interposed between the inner stylet slider and the proximal end wall; and a cocking mechanism; characterised in that the sub-frame has a first rack gear and the cocking mechanism includes a cocking slider, a pawl, and a rotary gear, the cocking slider having a second rack gear, the rotary gear being interposed between the first rack gear of the sub-frame and the second rack gear of the cocking slider, the pawl having a proximal end, a distal end and a mid-portion between the proximal end and the distal end, the mid-portion of the pawl being configured to rotatably mount the rotary gear, the pawl configured to interact with each of the cutting cannula slider and the inner stylet slider.