Paul, I see bullet weights ranging between 240 grain and 310 grains. It is quite normal for the POI to shift higher as bullet weight increases, so what you are observing is in part due to the weight of bullets you are loading with. However, that said the 240 grain bullet is pretty much a "standard" for the 44 Magnum and Special and if you have to bottom out your sights to get near center a shorter rear sight is in order. I would suggest that you to your tuning to get a good center hit with your 310 grain bullets with the sight bottomed, that should leave to a lot of adjustment lattitude for lighter bullets which will tend to shoot lower.