A buddy of mine makes his own bullets and reloads them they are made from a ceramic with a copper or steel jacket some times he makes them with a steel core (4.5mm steel cone) in front of an aluminum cylinder with a cavity in the rear like a bow tail the steel offsets the balance of the bullet so that the majority of its weight is near the front. he claims this steel core not only gives it the same grain number as match grade ammo but the distribution makes it more accurate.