This was the area I did not do well in at my E-5 board. It might have been because it was the MP Det. SGM asking me situational questions on the M16 weapon and range, or because I paid too much attention to all the details of the M16 and M4 rifles as well as the M9 and M11 pistols. If I had to do that board again, I would have shifted my focus to the basics of M16/4 operation, statistics and maintainence; then I would have paid particular attention to how it is utilized on the range and in combat. Not sure how or if this can help you, just wanted to add my thoughts.