I can see that the actual aiming is VERY hard to measure. Think about getting your gun out to that final position. If you move left or right or up or down 1/4" Mantis can sense that. If you twist the gun 1deg left or right, especially w/ the sensor hanging off the bottom of the mag, how can it sense that? This 'might' be an indicator that hanging the sensor below the barrel would be better. As you twist the gun that 1deg, the sensor would move sideways which I suspect it could notice.