The Synthetic Jacket Revolution: Coated Bullets On The Rise

For centuries, bullets were nothing more than plain lead balls. These lead balls morphed into more efficient shapes as muzzleloading guns and paper cartridges continued to evolve. The tail end of the 19th century saw a massive jolt in small-arms innovations, not just with repeating action designs, but also with metallic cartridge casings and propellant development. Lead balls gave way to shaped slugs, which shifted into sleek and pointy bullets.

Following new cutting-edge propellants, gilded-metal jackets became necessary to protect the lead cores of projectiles from the increasing pressures and velocities never before seen. Exposed, pure lead is too soft and can smear and foul the bore, affecting not only accuracy but also reliability. As a result, ammunition makers across the globe either jacket or plate ammunition with thin layers of metals that were harder than lead—typically copper. In short, the goal was to project the bullet with a thin external material that was harder than lead but not harder than the steel in the gun’s bore.