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A double-barreled shotgun is a
break-action shotgun
A shotgun (also known as a scattergun, or historically as a fowling piece) is a long gun, long-barreled firearm designed to shoot a straight-walled cartridge (firearms), cartridge known as a shotshell, which usually discharges numerous small p ...
with two parallel
barrels
A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden staves and bound by wooden or metal hoops. The word vat is often used for large containers for liquids, u ...
, allowing two
single shot
Single-shot firearms are firearms that hold only a single round of ammunition, and must be reloaded manually after every shot. The history of firearms began with single-shot designs, then multi-barreled designs appeared, and eventually many cent ...
s to be fired in quick succession or simultaneously.
Construction
Modern double-barreled shotguns, often known as ''doubles'', are almost universally
break action
Break action is a type of firearm action in which the barrel or barrels are hinged much like a door and rotate perpendicularly to the bore axis to expose the breech and allow loading and unloading of cartridges. A separate operation may be requir ...
, with the barrels hinge down at the rear to expose the breech ends for unloading and reloading. Since there is no
reciprocating action
Action may refer to:
* Action (narrative), a literary mode
* Action fiction, a type of genre fiction
* Action game, a genre of video game
Film
* Action film, a genre of film
* ''Action'' (1921 film), a film by John Ford
* ''Action'' (1980 fil ...
needed to eject and reload the
shells, doubles are more compact than repeating designs such as
pump action
Pump action or slide action is a repeating firearm action that is operated manually by moving a sliding handguard on the gun's forestock. When shooting, the sliding forend is pulled rearward to eject any expended cartridge and typically to coc ...
,
lever action
The toggle-link action used in the iconic Winchester Model 1873 rifle, one of the most famous lever-action firearms
Lever-action is a type of action for repeating firearms that uses a manually operated cocking handle located around the trigger g ...
,
bolt action
Bolt-action is a type of manual firearm action that is operated by ''directly'' manipulating the bolt via a bolt handle, which is most commonly placed on the right-hand side of the weapon (as most users are right-handed).
Most bolt-action ...
, or
self-loading shotguns.
Barrel configuration
Double-barreled shotguns come in two basic configurations:
* side-by-side (S×S) — the two barrels are arranged horizontally;
* over-and-under (O/U) — the two barrels are arranged vertically.
The original double-barreled guns were nearly all S×S designs, which was a more practical design for
muzzleloader
A muzzleloader is any firearm into which the projectile and the propellant charge is loaded from the muzzle of the gun (i.e., from the forward, open end of the gun's barrel). This is distinct from the modern (higher tech and harder to make) design ...
s. Early
cartridge
Cartridge may refer to:
Objects
* Cartridge (firearms), a type of modern ammunition
* ROM cartridge, a removable component in an electronic device
* Cartridge (respirator), a type of filter used in respirators
Other uses
* Cartridge (surname), a ...
-firing shotguns also used the side-by-side action, because they kept the exposed
hammer
A hammer is a tool, most often a hand tool, consisting of a weighted "head" fixed to a long handle that is swung to deliver an impact to a small area of an object. This can be, for example, to drive nails into wood, to shape metal (as w ...
s of the earlier muzzleloading shotguns from which they evolved. When
hammerless
A hammerless firearm is a firearm that lacks an exposed hammer or hammer spur. Although it may not literally lack a hammer, it lacks a hammer that the user can pull directly. One of the disadvantages of an exposed hammer spur is the tendency to ...
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. Some shotgun
shooting sport
Shooting sports is a group of competitive and recreational sporting activities involving proficiency tests of accuracy, precision and speed in shooting — the art of using ranged weapons, mainly small arms (firearms and airguns, in forms such ...
s, such as
skeet shooting
Skeet shooting is a recreational and competitive activity where participants use shotguns to attempt to break clay targets which two fixed stations mechanically fling into the air at high speed and at a variety of angles.
Skeet is one of the t ...
, use crossing targets presented in a narrow range of distance, and only require one level of choke. Other sports, like
sporting clays, give the shooter targets at differing ranges, and targets that might approach or recede from the shooter, and so must be engaged at differing ranges. 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 disadvantage lies in the fact that 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". For the side-by-side configuration, the shotstring continues on its path to the opposite side of the rib after the converging point; for example, the left barrel's discharge travels on the left of the rib till it hits dead center at 40 yards (36.58 m) out, after that, the discharge continues on to the right. In the over-and-under configuration with a parallel rib, both barrels' discharges will keep to the dead center, but the discharge from the "under" barrel will shoot higher than the discharge from the "over" barrel after 40 yards (36.58 m). Thus, double-barreled shotguns are accurate only at practical shotgun ranges, though the range of their ammunition easily exceeds four to six times that distance.
Side-by-side shotguns are often more expensive, and may take more practice to aim effectively than a over-and-under. The off-center nature of the recoil in a ''S×S'' gun may make shooting the body-side barrel slightly more painful by comparison to an over-and-under, single-shot, or pump-action, lever-action shotgun. Gas-operated and Recoil-operated, designs will recoil less than either. More side-by-side than over-and-under guns have traditional "cast-off" stocks, where the end of the buttstock veers slightly to the right, allowing a right-handed user to point the gun more easily.
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, for instance on a skeet, trap or hunting clays course when another shooter is firing; if the action is open, the gun cannot fire. Similarly, doubles are more easily examined to see if loaded than pump or semi-automatic shotguns, whose bolt must be opened and chamber closely examined or felt to make sure it is unloaded; with a double gun (or a break-action single gun), whether the gun is loaded, i.e., has cartridges in any chamber, is easily and immediately seen with a glance (and just as easily unloaded).
Trigger mechanism
The early doubles used two
trigger
Trigger may refer to:
Notable animals and people
;Mononym
* Trigger (horse), owned by cowboy star Roy Rogers
;Nickname
* Trigger Alpert (1916–2013), American jazz bassist
* "Trigger Mike" Coppola (1900–1966), American gangster
;Surname
* Bru ...
s, one for each barrel, located front to back inside the
trigger guard
A trigger guard is a protective loop surrounding the trigger of a firearm designed to prevent unwanted contact with the trigger, which may cause an accidental discharge. Other devices that use a trigger-like actuator mechanism, such as inhalers, c ...
. The
index finger
The index finger (also referred to as forefinger, first finger, second finger, pointer finger, trigger finger, digitus secundus, digitus II, and many other terms) is the second digit of a human hand. It is located between the thumb and the mid ...
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 two-ounce 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
Clockwork refers to the inner workings of either mechanical devices called clocks and watches (where it is also called the movement) or other mechanisms that work similarly, using a series of gears driven by a spring or weight.
A clockwork mec ...
type system, where a cam alternates between barrels, or by an
inertia
Inertia is the idea that an object will continue its current motion until some force causes its speed or direction to change. The term is properly understood as shorthand for "the principle of inertia" as described by Newton in his first law ...
l system where the recoil of firing the first barrel toggles the trigger to the next barrel. A double-barreled shotgun with an inertial trigger works best with full power shotshells; shooting low recoil shotshells often will not reliably toggle the inertial trigger, causing an apparent failure to fire occasionally when attempting to depress the trigger a second time to fire the second barrel (this also can happen if the first shell fails to fire). Generally there is a method of selecting the order in which the barrels of a single selective trigger shotgun fire; commonly this is done through manipulation of the
safety
Safety is the state of being "safe", the condition of being protected from harm or other danger. Safety can also refer to risk management, the control of recognized hazards in order to achieve an acceptable level of risk.
Meanings
There are ...
, pushing to one side to select top barrel first and the other side to select bottom barrel first. In the event that an inertial trigger does not toggle to the second barrel when firing low recoil shotshells, manually selecting the order to the second barrel will enable the second barrel to fire when the trigger is depressed again.
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 (which will inevitably destabilize the gun from the shoulder position and affect aim), and can utilize different chokes for the two shots (assuming, of course, that full power shotshells are fired, at least for a double-barreled shotgun with an inertial type single selective trigger, as needed to toggle the inertial trigger). This can be noticeably faster than a pump 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 (as there are no
bolt movements to delay the rechambering of a second shell). Note, however, in neither the pump or semi-automatic will the second shot be a different choke pattern from the first shot, whereas for a double, the two shots are usually with different chokes. Thus, depending on the nature of the hunt, the appropriate choke for the shot is always at hand. For example, while field hunting flushing birds, the first shot is usually closer than the second because the bird flies away from the shooter; so, the more open choke (and barrel) would be better for the first shot, and if a second shot is needed, as the bird is flying away, the more closed (and thus longer distance of an effective shot pattern) choke (and barrel) is then appropriate. Conversely, on a driven hunt, where the birds are driven towards the shooter, the closed (longer effective distance) choke (and barrel) should be fired first, saving the open (closer effective distance) choke (and barrel) for the now-closer incoming bird. None of this is possible with single-barrel shotguns, only with a double, whether S×S or O/U.
Regulation
''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. 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. Generally the shotguns are regulated to hit the point of aim 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. The regulation is usually more important in side-by-side than over-and-under shotguns, as felt recoil differs.
See also
*
* - Type of double-barrel shotgun from the American Old West
*
*
* - Type of rifle with two barrels mounted parallel to each other
*
*
* - Type of repeating shotgun with two barrels and each barrel has its own tubular magazine to feed from.
References
{{USCWWeapons
Break-action shotguns
Double-barreled shotgun
Multiple-barrel firearms