WW 231 IS a ball powder.
Ball powder describes the manufacturing process, not the powder itself.
During manufacturing, ball powders are often shape altered to varying degrees to control the burning characteristics.
In the case of 231, the shape altering produces what appear to be flakes, but which are simply flattened balls.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.