Star Bullet

If that star used to be on the inside and that's a civil war bullet, then it's fairly common.

I assumed the same thing bear. If that is the case, this bullet has been turned completely inside out. Interesting...

The star on the nose of the bullet is probably a sprue mark left from the mold. It looks different from the star that is inside the other bullet. When casting bullets, air must escape from the mold to allow it to fill with lead, and to be fully topped off with molten metal. Single bullet molds usually have a built in sprue cutter. Multiple molds have vents as well as a sprue depending on design. The star imprint also does not affect the flight of the round.