Derringer

[3] All were single-barrel pistols with back-action percussion locks, typically .41 caliber with rifled bores and walnut stocks.

The term "derringer" (/ˈdɛrɪndʒər/) became a genericized misspelling during the reporting of the Lincoln assassination, which was committed with a concealed Philadelphia Deringer.

[4] The ancestor to the deringer of the Old West was the boxlock overcoat pistol used by travelers from the late 18th century onward as protection from highwaymen.

Originally made as flintlocks, later versions used cap and ball ignition and sometimes featured turn-off barrels for faster reloading.

These served as the forerunner to the Old West gambler's over-and-under deringer and also to the pepperbox revolver with the addition of a ratchet to mechanically rotate the barrels.

A popular concealed carry handgun of the era, this pocket pistol design was widely copied by competitors, sometimes down to the markings.

[9] For loading a Philadelphia Deringer, one would typically fire a couple of percussion caps on the handgun, to dry out any residual moisture contained in the tube or at the base of the barrel, to prevent a subsequent misfire.

[3] All were single-barrel pistols with back action percussion locks, typically 0.41-inch (10 mm) rifled bores, and walnut stocks.

Barrel length varied from 1.5 to 6 inches (38 to 152 mm), and the hardware was commonly a copper-nickel alloy known as "German silver".

The most famous Deringer used for this purpose was fired by John Wilkes Booth who assassinated United States President Abraham Lincoln at Ford's Theatre in Washington, D.C., on April 14, 1865.

This particular model featured a hammer that also drew back the breach block and lifted a new cartridge out of the magazine upon cocking.

A military pistol that is a deringer design is the FP-45 Liberator, a .45 ACP insurgency weapon dropped behind Axis lines in World War II.

Due to this limitation, it was intended for short-range use (1–4 yards (1–4 m)) either as a last-ditch self-defense gun or to sneak up on and kill an unsuspecting Axis soldier to steal a more serviceable weapon.

These double-barrel derringers were chambered for .22 Long Rifle and .22 Magnum and were available in blued, nickel, silver, and gold-plated finishes.

Although they were discontinued in 1984, American Derringer obtained the rights to the High Standard design in 1990 and produced a larger, .38 Special, version.

[18][better source needed] They feature stainless steel ported barrels and aluminum or titanium alloy frames.

[19] Its makers have stated that they drew inspiration from the FP-45 Liberator pistol, which also held extra ammunition in the grip.