Back to school for you. Good thing this was only a practice test.
You should have dialed in nearly 30 (1/4 inch) clicks.
Try using this ballistic calculator and see if if does better and if not then we will go through your input data one piece at a time till we find where you are making a mistake.
I used an elevation of 4000 ft and a temperature of 45 degrees and a sight height of 1.5 inches all with a 100 yard zero to get a drop of 7.5 MOA.
JBM - Calculations - Trajectory