[husky ed]

The clicks on the the sights are in M.O.A. : Minute Of Angle

Which can be either 1/4 M.O.A., 1/2 M.O.A., 1 M.O.A., ect.

Of course 1/4 M.O.A. is the finest setting.

Also the scope would be calibrated for the caliber of bullet that is being shot, in this case .308/7.62mm and in meters or yard.

M.O.A. can be describe as 1 inch wide at 100 yards, 2 inch wide at 200 yards and so forth.
Therefore 1/4 M.O.A. would be 1/4 inch guoup at 100 yards.

I realize this is on the simple side, but I'm a simple guy.

Hope it helps.

[husky ed]

I should have said 1/4 M.O.A. is the finest setting in this example. There are others.

[spodefly]

I am familiar with MOA and the various manufacturers using different MOA movements per click. My Leupold is 1/4 MOA, I believe ... either way, it took me around 8 shots to initially zero in at 200 yards because I was being too conservative on the number of clicks I was using to move it to the right.

Here in Georgia, because of the thickness of the woods, shots beyond 300 yards are rare. There are a few fields I hunt over where I might have a 400 or 500 yard opportunity, but that has only happened once in 25 years, where I had a buck out at about 500 yards. (I missed, by the way, with the bullet hitting short, and probably going right under him.)

A Marine friend of mine from California came here to hunt once, and he missed every shot because his .308 was sighted in at 500 yards ... he was shooting over everything at the 150 yard ranges that are typical here. He caught all sorts of hell for it too ... ;)

The bullet drop out past 500 yards starts to get really steep, and considering the wind was described as 'gale force' during the shot referenced in the article, I suspect that the 56' arc is not too far from the truth.