A device affixed to the muzzle of a shotgun to increase overall barrel length is typically called a muzzle device or attachment. These attachments serve various purposes, from improving accuracy and recoil management to altering the shotgun’s sound signature. They can range from simple choke tubes to more complex muzzle brakes or compensators.
Longer barrels can offer several potential advantages, including improved sight radius and potentially tighter shot patterns at longer ranges. Historically, longer barrels were favored for hunting waterfowl and other game requiring longer shots. Modern advancements in ammunition and choke design have somewhat diminished this advantage, but extended barrels remain a popular choice for some shooting disciplines. Their impact on performance varies depending on the specific attachment, the shotgun itself, and the ammunition used.