Just bought a Springfield Arms 40 XD in .40 S&W...the ported version..Question, it shoots a little low using the target on top of the front sight system of aiming at 10 yards..about 4 inches..using 180 JHP over 8.8 grains of Blue Dot...I need to raise the point of impact about four inches...I tried dropping the powder charge down to 8.0, it helped but not enough..Question is should I go to the lighter 155 bullets or the heavier 200 grainers...which should have a higher point of impact..all of this could have been solved if they'd put some adjustable rear sights on the great pistols..."THANKS" for your help and experience with solving this problem..I realize that I could just change my aiming point to compensate for the difference but I was just wondering if it could be solved with bullet weight and velocity change somehow...

Heavier bullets normally shoot higher then lighter ones. or you could replace front sight with a lower one.

File off the front sight, a bit at a time.
Peter.

I had the same problem. I now only use 155 horn. and longshot. 2" 5 shot groups to point of aim at 25 yds.
HTH
Don55