My rangefinder sucks when it comes to ranging pretty much anything in the Eastern Colorado plains when I am out Antelope hunting. It is a Nikon 550. It works great out to 500 yards when I am elk hunting in the mountains, but I can hardly get out to 150 yards when there is nothing but dry grass. I have used my scope in the past to get a ballpark for how far away the antelope are, but don't trust my experience level for ranging far. What gear/techniques do all of you use when you are antelope hunting, especially for long range shots?