I am not familiar with the type of gravel that you are referring to by number. In this part of the country (New England) gravel is stone with course sand mixed in and it is strip mined from gravel pits. If you have only one size of stone, and try to compact it, without anything being between the stone, it will always have a tendency to shift. If what you are referring to is crushed rock, then the sharp corners of the crushed rock will intertwine and cause it to become more of a monolithic structure. Building practices and terms are very regionally determined, so we would need more information and possibly pictures to help give guidance.
