This is a hypothetical question that I am curious about.. Suppose we are trying to design a projectile that is intended to travel at high hypersonic velocities, on the order of mach 10 or 20, through air (you can assume sea-level density for argument's sake). Would an ideally sharp round projectile, shaped like this: () , (i.e. with pointed nose and tail, somewhat like a fat version of an olympic spear), have a lower drag coefficient at such velocities than the standard tear shape (i.e. with a rounded nose and sharp tail), in theory? If not, what would be the most efficient shape for this case? I'm thinking that if both ends of the projectile are ideally sharp (to atomic level or close to it), then this should be able to cut though the air with minimum turbulence. But at high hypersonic velocity there are probably various effects that I'm not familiar with, and even at subsonic speeds I'm not really qualified to answer this question.. EDIT: Forgot to ask - what would be the drag coefficient of such a shape (the most efficient one), more or less?