Qualification for the course includes 42 rounds on target between 300-600 meters, with a minimum of 10 at each distance.
I can kinda see and hit 600 meters, it’s just a bitch and a half. With an ACOG I could plop rounds on target at 600 easy. Qual is with iron sights.
600+ is when we break out the 7.62 EBR.
Max effective range for an M16 is 550 meters, So this is just slightly pushing the envelope.