Historically, an average cadet may take around 15 credit hours. However, some others may take anywhere from 12 to 20 credit hours.
Depending on your major and your graduation year, this number can vary significantly. Here at the University of Akron Army ROTC, we do not recommend students to "course overload" which is typically anything over 15 credit hours. This is due to the heavy demands it places on the students and historically always ends up with the cadet dropping a class or two.
If you plan and follow your course requirements by utilizing the Planned Academic Worksheet (CC-104R), this can mitigate a lot of issues such as taking a semester full of core classes.