If I understand your sighting situation, you are pulling the front sight blade half way down into the "V" of the rear sight to be spot on at 100 yards. If you were to align the front sight level with the top of the rear sight's notch, you'd shoot high.
You need to file off the top of the rear sight until when the front sight is level with the top of the rear sight, and centred in the notch left and right, your shot hits centre, at whatever range you choose as your point blank.
Currently, I file my sights so that I am spot on at 50 meters, holding the front sight level with the notch/top of rear sight. This gives me a clean sight picture for 25 meters or ten, if it's a tack or string that's the target, and I hold front sight above the notch, front sight centred on the target, for 100 meters. As an example, on my 50 cal. rifles, I have filed a bevel of about 45 degrees on the back corner of my front sight blade, creating a little square of silver. Looking down the barrel, this little square turns into a ball of silver light. At 100 meters, I simply place the shiny silver "ball" on top of the rear sight's notch, hold centre on the target and touch it off. For most of my shooting which is at steel clangers, this is fine enough accuracy to achieve hits most of the time.