Cup and Core
The traditional bullet built from a drawn jacket cup around a swaged lead core, the basis of most match and hunting projectiles.
A cup and core bullet begins as a thin metal cup that is drawn and formed into a bullet jacket, then has a soft lead alloy core swaged inside it. The jacket and core are held together only by friction and forming pressure, not by any chemical bond, which keeps the design simple and inexpensive to make in large numbers.
This construction is the foundation of most match and hunting bullets in production today, from open-tip target designs to the jacketed soft point used on game. Because the core is not bonded, a cup and core bullet can shed weight or separate under hard impact, which is the tradeoff handloaders weigh against its accuracy and low cost.