Double-Barreled Shotgun

Lore & Background

Double-barreled shotguns come in two basic configurations: side-by-side (S×S), where the two barrels are arranged horizontally, and over-and-under (O/U), where the two barrels are arranged vertically. The original double-barreled guns were commonly all side-by-side designs, which was a more practical design for muzzleloaders. Early cartridge-firing shotguns also used the side-by-side action, because they kept the exposed hammers of the earlier muzzleloading shotguns from which they evolved. When hammerless designs started to become common, the over-and-under design was introduced, and most modern sporting doubles are over-and-under designs. One significant advantage that doubles have over single-barrel repeating shotguns is the ability to have more than one choke at a time. Having two barrels lets the shooter use a more open choke for near targets, and a tighter choke for distant targets, providing the optimal shot pattern for each distance. The barrels of a double-barreled shotgun, whether over-and-under or side-by-side, are not parallel, but slightly angled, so that shots from the barrels converge, usually at 40 yards out. Double-barreled shotguns are also inherently more safe, as whether the shotgun is loaded or can be fired can be ascertained by anyone present if the action is broken open.

In Their Own Story

The early doubles used two triggers, one for each barrel, located front to back inside the trigger guard. The index finger was used to pull either trigger, as having two fingers inside the trigger guard can cause a very undesirable recoil-induced double-discharge. Double-trigger designs are typically set up for right-handed users. In double-trigger designs, it is often possible to pull both triggers at once, firing both barrels simultaneously, though this is generally not recommended as it doubles the recoil, battering both shotgun and shooter, particularly if it was unanticipated or unintended. Discharging both barrels at the same time has long been a hunting trick employed by hunters using 8 gauge 'elephant' shotguns, firing the two 875 gr (56.7 g) slugs for sheer stopping power at close range. Later models use a single trigger that alternately fires both barrels, called a single selective trigger or SST. The single selective trigger does not allow firing both barrels at once, since the single trigger must be pulled twice in order to fire both barrels. The change from one barrel to the other may be done by a clockwork type system, where a cam alternates between barrels, or by an inertial system where the recoil of firing the first barrel toggles the trigger to the next barrel.

Reader's Guide

Regulation is a term used for multi-barreled firearms that indicates how close to the same point of aim the barrels will shoot. A poorly regulated gun may hit consistently with one barrel but miss consistently with the other, making the gun nearly useless for anything requiring two shots. Regulation is necessary due to barrel yaw; absolutely zero yaw, in which both barrels fire perfectly straight and their lines of fire are perfectly parallel, will never happen in practice, and the barrels both shooting wide is not useful, so the gun is regulated to have the lines of fire converge at some point in front of the muzzle at a given distance, usually the maximum expected range since that is the range at which a full choke is used and where precise regulation matters most. However, the short ranges and spread of shot provide a significant overlap, so a small error in regulation in a double is often too small to be noticed. Regulation is usually more important in side-by-side rather than over-under shotguns, as felt recoil differs. One of the advantages of double-barreled shotgun with double triggers or single selective trigger, is that the second shot can be taken almost immediately after the first with merely a second trigger pull, without needing to manually operate the action, and can utilize different chokes for the two shots. This can be noticeably faster than a pump-action shotgun, which requires manually pumping the fore-end to eject and reload for the second shot, and may be faster, or not slower, than a semi-automatic shotgun.

Did You Know?

• Double-barreled shotguns are almost universally break action, with the barrels hinging downward to expose the breeches for loading and unloading.
• The barrels of a double-barreled shotgun are not parallel but slightly angled, so shots converge usually at 40 yards out.
• In double-trigger designs, it is possible to pull both triggers at once, firing both barrels simultaneously, though this doubles the recoil.
• A double-barreled shotgun with an inertial trigger works best with full power shotshells; low recoil shotshells often will not reliably toggle the inertial trigger.
• Regulation is necessary due to barrel yaw; a poorly regulated gun may hit consistently with one barrel but miss consistently with the other.