There is likely no other firearm with as diverse a range of suitable applications as the shotgun. These include military operations, law enforcement, hunting, sports such as trap and skeet shooting, as well as personal and home defense. Shotguns come in a wide variety of sizes generally referred to by a unit of measurement known as the “gauge.” Some of these include 16 gauge, 20 gauge, 12 gauge, and 10 gauge; the smaller the number, the larger the bore diameter. Shotgun shells can be loaded with a multitude of projectiles, ranging from small to large diameter shot, slugs and various mission-specific loads.
Ask any gun shop or firearm instructor - if you had to own just ONE firearm, what would it be? They would all likely say that it should be a shotgun.