Duca, the front sight is filed with two angles on the back side. I usually have to play with the adjustment (filing), but the idea is the part on top of the backside is filed so the coin silver catches the light and the bottom part filed at the different angle is shaded. On long shots I can sight with the shiny part above the rear sight notch without having to hold so high on the target, still keeping the bulls eye in the sight picture. Make sense?
I know it's not PC but neither are sights this high on a long rifle. I learned about heat waves on my first build that I put traditional PC low sights on and had to change them to shoot a match.
Mountain man, I told myself I wasn't going to start another rifle build till I got some little projects done I've wanted to do. Boxes, horns, knives, bags, etc..,. but that other barrel is lying in the rafters of the shop right over my work bench and every time I walk in there it calls out to me. It's sort of like a little puppy whining for your attention. It's hard to ignore it.