An end stop detection method for a powered surgical instrument having a hand-held surgical instrument, an end effector and a shaft assembly including a drive member, a flag member, and a sensor, the method comprising: controlling a motor within the hand-held surgical instrument to cause the drive member to rotate in a first direction thereby causing the flag member to translate axially along the drive member toward the sensor determining when the flag member contacts the sensor and stopping the motor when the flag member contacts the sensor.