A cartridge comprising a bullet, the bullet providing a radially expanding array of bullet fragments upon entering a target and also providing an increase in effective surface area of the bullet within the target by structural features that facilitate tumbling or mushrooming in the target. In an embodiment a pair of axial core members are aligned in a bullet jacket with the forward core member being segmented with separation junctures formed by engaged faces of adjacent segments. Impact causing fracturing of the segments from a base portion.