Son just bought me a Bushnell Banner Dusk&Dawn 4 Plex, Mil-dot, 3-9x50E. Just looking for an explanation on all the marking on the reticle (inside of the scope) I understand the cross hairs and how to set elevation & windage (scope is sighted in at 200), but the graduation just under them (are they distance marking? if so what distance?) and the curve lines at the bottom of the scope. Nothing mention in the instruction that came with it.

Simply put, the Mil-Dot is a way to estimate range with the scopes reticle. This type of reticle was developed for military applications. The space between the dot centers is equal to one milliradian (Mil). hence the name mil-dot. One Mil equals 3.6" inches at 100 yards, or 36" at 1,000 yards. To use this system effectively you must know the size of the target. For instance most people are an average of 6 feet tall or 2 yards. The formula used for determining range to the target is (size of target x 1000 divided by number of mils the target covers). Hope this helps FixYa up.