I'm having a problem with my truglo TFO sights I installed in my sig p226 elite dark. I installed the 8front 8rear sights and it seems to shoot very low. Is this normal or bad. Because when I aim all three dots in sync the round goes about 4 inches low at 30 feet or so. Haven't been able to do up close shots but this is very aggravating seeing as I have to aim above the target to hit the target and don't know where l hitting because the gun is blocking my view. Waste of money if there is no correction for this. I emailed truglo but no response yet.