I picked up a CAI .45 commander size to start tinkering with and learn how to do some of my own work. The barrell bushing that was on it didnt fit right so I bought a new on got it to fit up right evreryting is working well but the gun hits 6" low at 15yrds groups are good but Im not sure if I did something wrong while installing? I must also say that I didnt put any rounds threw it before and I didnt take the old barrell bushing to the range to see if it had any affect. It has original combat type sights so there really is no quick adjustment to be had there. Any ideas ???