 This is not ideal for ballistics, especially supersonically where a higher fineness ratio is desirable.Bull solved this problem by using an additional set of nub "fins" near the front of the shell to keep it centered in the barrel, allowing the driving band to be greatly reduced in size, and located wherever was convenient.Re-shaping the shell for better supersonic performance provided dramatically improved range and accuracy, up to double in both cases, when compared to a similar gun using older-style ammunition.