This article has been updated to include additional source commentary.
It’s difficult to resist raising an eyebrow at an Oklahoma robbery suspect’s alleged recent weapon-of-choice. According to several Oklahoma news outlets including WKTUL, a 24-year-old man was arrested on December 6 by Tulsa police after allegedly robbing a liquor store using what employees described as an “old-timey musket.”
Authorities soon apprehended and charged the suspect before providing some additional details about the weapon.
“For those who are curious, the firearm is likely from the mid-1800s and is a single-shot percussion Derringer. It was also called the ‘Muff Pistol’ or ‘Pocket Pistol,’” Tulsa police posted to social media on December 8.
Definitely not a derringer
According to firearms historian Michael Helms, law enforcement’s initial assessment is slightly off target—regardless of whether you spell “Derringer” with one “r” or two.
“‘Derringer’ properly refers to a gun made by Henry Deringer, who was a Philadelphia gunmaker that developed a reputation for his compact percussion pistols,” Helms tells Popular Science. “Deringer’s name came into widespread use when one of his pistols was used to assassinate Abraham Lincoln. Over time the ‘Derringer’ name became a genericized term for small percussion pistols.”
While cautioning that it’s difficult to assess a historical firearm from a single photo, Helms didn’t see any immediate evidence to suggest the weapon is a replica. Tulsa police were correct in designating it a percussion pistol. These types of guns are loaded from the muzzle with a ball and powder and primed using a percussion cap. At the same time, there is also something striking about the crime scene evidence.
“This pistol is something a bit different and somewhat rarer; this is an ‘underhammer’ pistol,” said Helms. Conventional mid-19th century weapons usually featured hammers located on either the top or side of the gun. As the name suggests, underhammers have the hammer positioned underneath the gun barrel.
“In this case, the hammer is attached to the forward trigger, which was used to ‘cock’ the gun. The trigger behind it would have released the hammer and fired the gun,” he added.
Underhammer guns aren’t traceable to a single person or era, but firearm historians do credit its popularization to Nicanor Kendall. The gunmaker lived in Vermont during the 1840s and 1850s, and developed his own underhammer safety lock after his own pistol misfired while attempting to shoot a squirrel.
While he said the weapon’s overall design is “pretty generic,” Helms theorizes it could have been produced by Ethan Allen. Not to be confused with the furniture company or the leader of the Green Mountain Boys during the American Revolution, this Ethan Allen was a prominent 18th century arms maker who patented numerous single- and multi-shot pistols.
A likely suspect
However, after examining the available photo, firearms historian Ashley Hlebinsky believes that the answer is pretty clear.
“It looks like a Bacon & Co. Underhammer Pistol,” she tells Popular Science. Although Hlebinsky admits it’s hard to conclusively determine the maker without examining the markings in person, the gun “looks identical” to firearms produced between 1850 and 1857 by the Connecticut-based company.
Hlebinsky’s theory is further strengthened by the fact that Thomas Bacon himself previously worked with Ethan Allen. The Bacon & Co. underhammer pistols were .34 caliber weapons featuring either a 4- or 5-inch barrel and broad, floral decorative engravings. If corroborated, then the Tulsa robbery weapon is one of only 500 ever manufactured, and has recently sold for as much as $850.
In the end, there are a few reasons why only a handful of the guns were produced, with technological innovation being the primary explanation.
“With the development of the metallic cartridge revolver in the late 1850s, the architecture of guns changed considerably, and by the 1860s and 1870s the underhammer design (and the percussion lock in general) was largely obsolete,” said Helms.
Today, underhammer firearms are often considered collector’s items. Helms noted while many American and like some European gunmakers “dabbled with these designs,” they arrived late in the percussion pistol’s development and didn’t affect wider arms production.
“All the same, this is an interesting antique pistol,” Helms conceded.
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