I have a Wesson and Harrington BC with a set of 45-70 and 38-55 barrels. I have an old Marble's Tang sight mounted on mine, so it's not a really tall one. It's probably only about three inches tall at best. I believe I get a total of 81 or 85 clicks vertically with it.
With 500 grain bullets and medium loads, I can reach just over 100 yards at full height. With 300 grains, I can get out to about 150 or so, maybe more.
With the 38-55 barrel mounted, the sight at full height, and 264 grain bullets (284 grain, actual weight) I can get out to about 350 yards with the sight at full height.
I typically use the largest eye cup with the smallest aperature in the rear sight and a larger size circle in the front when target shooting. If shooting "stuff" such as little critters etc, I use the larger eye cup aperature with a straight vertical front sight mounted. With the target sights mounted in, it's hard to see a critter, hence why I change the set of sights for plinking/hunting.
I hope that helps.