The GG&G MAD BUIS with ranging aperture has a disc in the rear sight with different apertures in  it that are calibrated for varying distances.  The aperture marked "0" is supposed to be the 25 yard and 200 yard zero, the one marked "3" is 300 yards etc.  The sight is supposed to be calibrated for bullet weights from 55gr - 62gr fired from a 16 inch barrel.  Can anyone explain to me how the "0" aperture can be zeroed for both 25 yards AND 200 yards ?  Every ballistics table and internet post I can find says that a 55gr round zeroed at 25 yards will "zero" again (on the downward arch of the trajectory) out around 350 yards, and that closer zero that "pairs" with 200 yards is 50 yards.

bump

I have wondered the same thing. I have always thought that it was a 50yd/200m zero, and a 25yd/300m zero, or something similar. I'm wondering if this is simply a typo on the website. Someone correct me if I"m wrong. Maybe I'm missing something.

me too

No, it's not a typo on the website. The same statement is in the instructions that came with the sight.  I contacted GG&G and they were adamant that the 25 yard zero would be right on at 200 as well.  I asked if they had a reference they could point me to or some data to back this up.  They were nice enough to send me a ballistic trajectory graph.  The only problem was that the curve for the 25 yard zero on the graph was more than 9 inches high at 200.  I pointed this out to the person who sent it to me.  They just kept insisting that I go and try it and that I would find that it works.