I use the duplex reticule in my scope to make fairly accurate range estimates. First I found out that a 6" bull at 100 yards fills the space occupied by the fine cross hairs at 5X. In other words 6 minutes of angle. When I spot game that looks far, far away, I set the scope at 5x and see how it fits in the reticule. An antelope with a back to chest measurement of about 15" will fill the space at 250 yards. A nice buck meauring 18" fills the space at 300 yards. A 24" elk at 400. I know the trajectory of my bullet from careful shooting at various ranges, not trusting my computer to tell me where the bullets will go. I sight in at 200 yards and adjust my hold for ranges beyond that. If they really get long, the bottom coarse hair gives me a post to aim with. It shoots 3 minutes of angle higher than the center of the crosshair. It sure beats payin' a lot of money for one of them range findin' scopes, or laser finders that don't work so good on soft targets. I can disagree with my guide and not be embarrased.