Which feature is NOT found in shotgun barrels compared to rifles?

In the context of shotgun barrels compared to rifle barrels, the defining characteristic that sets them apart is the presence of rifling grooves. Rifling refers to the spiral grooves cut into the bore of a rifle barrel that impart a spin to the bullet, stabilizing its flight for increased accuracy at greater distances. Shotguns, on the other hand, typically have smooth bores, which allows the shot (small pellets) to spread out upon firing rather than following a single path, making them more effective for shooting moving targets at shorter ranges.

The smooth internal surface of a shotgun barrel is key to its function, as it allows for the efficient passage of shots or slugs without imparting spin. In shotgun design, maintaining a consistent barrel width also plays a critical role; it ensures that the ammunition fits properly and that the spread is controlled. However, checkering on the grip pertains more to the handling of the firearm than barrel design itself, making it irrelevant to the fundamental features of shotgun and rifle barrels. Thus, the absence of rifling grooves in shotgun barrels is what distinctly differentiates them from rifles.