Rifle bullets are single, solid projectiles designed for precision. They're typically made of lead with a copper jacket, have an aerodynamic shape, and are significantly larger than individual shotgun pellets. Rifle bullets maintain their trajectory over long distances and are fired from barrels with spiral rifling that makes them spin for stability and accuracy.
Shotgun pellets, in contrast, are multiple small spherical projectiles (shot) contained in a single shell. When fired, these pellets spread out in a pattern, creating a wider impact area. They're typically made of lead, steel, or other materials and come in various sizes depending on the intended use. Shotgun pellets lose velocity more quickly than rifle bullets and are most effective at shorter ranges.
The key functional difference is that rifle bullets are designed for precision at longer ranges (often hundreds of yards), while shotgun pellets create a spread pattern for hitting moving targets at closer ranges (typically under 50 yards). This makes rifles better for single-target long-distance shooting and shotguns more effective for moving targets at closer ranges.