"Main Frame" is the "typical" antler configuration.
Someone may say his main frame score is xxx BC pts, for instance. He means the main beam, eye guards and the 3 pts coming off the main beam (tip of main beam is counted as a pt)Also the circumfrence and inside spread. No non typical pts are included.
A buck that has non typical points will be measured and refered to as (for instance) a 180" typical main frame. The added non typical pts will then be added to that for the non typical score.
Clear as mud, I'm sure....