Shotguns are classified by which measurement, used to describe their shells?

• A. Gauge
• B. Caliber
• C. Shell length
• D. Chamber pressure

Answer: (A)

The main idea here is how shotguns are sized and what term describes the shells they fire. Shotguns are classified by the bore size, told in terms of gauge. Gauge is a historic way of describing the diameter of the shotgun’s bore and, by extension, the size of the shells that are appropriate for that gun. In practice, a 12-gauge shotgun is designed to fire shells labeled as 12-gauge, and a 20-gauge gun uses 20-gauge shells. This gauge system is specific to shotguns and determines what shells will fit safely and perform correctly.

Caliber is the term typically used for rifles and handguns, describing bullet diameter in inches or millimeters, which isn’t how shotguns are classified. Shell length describes how long a particular shell is, not the size of the bore itself, and while it matters for fit and performance, it doesn’t define the gun’s classification. Chamber pressure relates to the force the shell generates and the gun’s pressure rating, not the way the firearm is sized or categorized. So the best answer is gauge, the measurement used to describe shotgun shells and their compatibility with the gun.