Autoreaming systems and methods

Methods and systems for controlling movement of a bit of a drilling assembly during reaming of an already-drilled hole; the methods, in certain aspects, including determining a ream speed for downward movement of the bit in the hole, moving the bit downward in a hole at said ream speed, determining a time period for deceleration of the bit to the hole bottom, determining a value for a target drilling parameter for drilling beyond the bottom of the hole, decelerating the bit (linearly or non-linearly) for the time period, and achieving the value for the target drilling parameter when the bit reaches the bottom of the hole.