I can easily hit a 24" Dong using the B&C out to 500yds (last mark when I'm zero'd @ 200yds). I can with the help of bag rest estimate the holdover and hit the 600yd dong 2-3 times out of 5 once I find the spot. ...
Does that make it an almost 5 minute of dong rifle?
Try turning your magnification ring down until the last aiming point matches your drop at 600 yards and mark it. Even at a lower power a dong that size will be easy to see...