Coach gun

A coach gun is a double-barrel shotgun, generally with barrels approximately 18" in length placed side-by-side. The name comes from the use of such shotguns on stagecoaches by shotgun messengers in the American Wild West and during the Colonial period of Australia.

Origins
The term "Coach gun" was coined in 1858 when Wells, Fargo & Co. began regular stagecoach service from Tipton, Missouri to San Francisco, California. They issued shotguns to its drivers and guards for defense along the perilous 2,800 mile route. The guard was called a shotgun messenger although the phrase riding shotgun was not coined until 1919.

There was no single manufacturer for the traditional coach gun, as it was a generic term describing a class of shotguns offered in a variety of barrel lengths from 12 to 20 in, either by the factory or from owners and gunsmiths cutting down the barrels.

Early manufacturers
These shotguns featured external hammers and were manufactured by Remington Arms, Ithaca, Wm. Moore & Co. Meriden, Buckley, Burgess, Colt's Manufacturing Company, Hunter Arms, Husqvarna, Lefever, Parker, Sharps Rifle Manufacturing Company, Savage-Stevens, Villegia, and Westly Richards to name a few.

Use in the Old West
Doc Holliday used a 10 gauge Wm. Moore & Co. coach gun to shoot Tom McLaury point-blank in the chest with buckshot during the Gunfight at the OK Corral in Tombstone, Arizona, on Wednesday, October 26, 1881. They stood in such close proximity that the town mortician was able to cover McLaury's wound with one hand."  Wyatt Earp also used both barrels of a 10 gauge coach gun to kill "Curly" Bill Brocius point-blank the next year.  Brocius's body was nearly severed at the midsection.

Modern makers
Modern coach guns are manufactured by Stoeger (Brazil), Boito (Brazil), Baikal (Russia) (which is now being distributed by Remington under the name Spartan Gunworks), Huglu Armsco (Turkey), Khan (Turkey), Diamond (Turkey), Rossi (Brazil), and a variety of Chinese companies for US distribution through Century International Arms and Interstate Armscorp.

Current usage
Modern coach guns are commonly encountered in Cowboy action shooting competitions, among collections of Western guns, as home-defense weapons, and even as "scrub guns" for hunting grouse, woodcock, rabbit, hare, and/or wild pig in scrub, bush or marshlands, where the 24"+ barrels of a traditional shotgun would prove unwieldy. The modern coach gun can be had in a variety of configurations suitable for both Cowboy Action Shooting competition and hunting.

Coach guns are similar to sawn-off shotguns but differ in that coach guns manufactured after 1898 are offered as new with 18" barrels and 26" overall length, and meet legal requirements for civilian possession in the USA. Australia, and New Zealand have slightly different laws for length, with NZ requiring a minimum overall length of 30" (anything shorter is considered a pistol) with no minimum barrel length and Australia requiring an 18" barrel and a 30" overall length. In the United Kingdom, however, shotguns must have a minimum barrel length of 24" to be eligible for ownership on a Shotgun Certificate, and shotguns with barrels under this length (which includes Coach guns) must be obtained on the more stringent Firearms Certificate. Some modern coach guns feature internal hammers as opposed to the traditional external hammers.