Originally Posted By: Trapper LukeAlright so I know that it stands for Adjustable Objective but what exactly does havin that AO do for a scope and shooter?
Thanks,
Luke
Luke,
The Adjustable Objective on scopes allows for you to focus the scope from it's minimum distance, out to infinity. That way, the parallax will be perfect for any shooting distance you set the AO for, and the cross hairs will also be in focus at that distance. For other distances, you will have parallax, and out of focus cross hairs..
Minimum distance for Leupold's Adjustable Objective scopes is 50 yards, except for two of their scopes that focus down to 25 yards; thses are their EFR scopes.
Non-Adjustable Objective scopes have the parallax pre-set at about 100 yards, or maybe slightly farther, like 125 yards. You must live with slight parallax at distances other than the 100 yards. However, if you keep your eye centered in the ocular lens, you'll have no problem with parallax shooting at any distance.
Parallax occurs when the image plane, and the reticle plane, inside the scope tube, do not coincide.
