An apparatus disclosed herein comprises a reader structure having a sensor stack and a bottom shield having a first end and a second end on opposite sides of the bottom shield in a cross-track direction, wherein the first end is formed by intersection of arcs. In one implementation, the apparatus disclosed herein the sensor has a bottom shield having a bullet shape with a first end along a cross-track direction being rectangular and a second end along the cross-track direction being formed by an intersection of arcs.