The classic text "兵法" is usually translated as "The Art of War", but doesn't "武術" also literally mean "art of war"?
My (not very long) experience with chinese language makes me believe that if there are two characters with the same english translation then almost always there are nuances of their meaning or usage.
So are there more precise translations for "兵法" and "武術"?
My guess is that since "兵"'s first meaning is a "soldier" and "法" is more like a "rule", "兵法" relates to the way you should organize your troops, learn about your enemy to prepare for battle etc, more like a "management of the army"; while "武術" actually means "the art of battling", "the art of fighting on the battle field". So that when the "兵法" part is done, you can use your "武術" to beat the enemy.