Servos are not precision devices and there will be variations between individual devices and between different models. Some can't physically sweep through 180 deg, some can go a bit more.
Your code should move the servo through 110 deg so I don't understand how you say it moves 180 deg.
Perhaps you mean that it goes all the way to the end stop at one end? In that case it probably isn't going all the way to the other end stop.
...R