Roland had been thinking about bullets for the revolving firearms. Circular lead bullets and loose gunpowder were an arrangement that was simply too backward. Taking Anna's ability into consideration, the direct manufacture of copper shells for ammunition was technically feasible. The key concern was that there did not have a reliable primer to ignite the black gunpowder in the cartridge for reliable firing.
In early times, the outer shell of the ammunition was generally made out of mercury fulminate which was extremely sensitive to impact. When one pulled the trigger, it would stimulate the firing pin, and hit the base of the bullet. The mercury fulminate would flare up, igniting the black powder, and eject the bullet from the chamber.
