I've a MATECH 200-600m back up sight on my AR (which is calibrated for M855, 62gr bullet out of M16A2/M4, around 3,100 fps). The genuine one will give you very close POI at those ranges with the right bullet weight and velocity. I like my MATECH sight as it's been in service for a while. But you can't see target very clear beyond 400m, just point and shoot.
(From FM3-22-9)
Appearance of Objects Method
7-264. This method of range determination is based on the size and visible characteristics of an object. To use this method with any degree of accuracy, the SDM must be familiar with the appearance and visible detail of an object at various ranges. Some common guidelines can be used to determine the range of a human target:
- At 200 meters, a human target is clear and details can be seen.
- At 300 meters, the target is still clear, but no details can be seen.
- At 400 meters, the target’s outline is clear; however, the target itself is blurry.
- At 500 meters, the body tapers and the head disappears.
- At 600 meters, the body resembles a wedge shape.
