Editing Double-barreled shotgun (section)

===Trigger mechanism===
The early doubles used two [[trigger (firearms)|trigger]]s, 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.<ref name="tbm"/> 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 {{convert|875|gr|g|abbr=on}} slugs for sheer stopping power at close range.{{citation needed|date=November 2017}}

Later models use a single trigger that alternately fires both barrels, called a ''single selective trigger'' or ''SST''.<ref>{{Cite book |last=Wiles |first=Laurie Bogart |url=https://books.google.com/books?id=ilaaDwAAQBAJ&dq=single+selective+trigger+or+SST&pg=PT252 |title=Shooter's Bible Guide to Shotgun Sports for Women: A Comprehensive Guide to the Art and Science of Wing and Clay Shooting |date=2022-08-02 |publisher=Simon and Schuster |isbn=978-1-5107-4504-9 |language=en}}</ref> 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 [[inertia]]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 (firearms)|safety]], 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-action shotgun, which requires manually pumping the [[forearm (firearm component)|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 (firearms)|bolt]] movements to delay the rechambering of a second shell). Note, however, in neither the pump-action 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, either a side-by-side (S×S) or over-and-under (O/U).