Williamson Deringer

Moore's Patent Firearms Co. · Pistol · Discontinued · 1866

Also known as: Williamson Derringer, Williamson's Patent Derringer, D. Williamson Single Shot Deringer

Overview

The Williamson Deringer is a single-shot, breech-loading pocket pistol chambered in .41 Short Rimfire, designed by David Williamson of New York City and manufactured from 1866 by Moore's Patent Firearms Company of Brooklyn, New York, and later by its successor the National Firearms Company. Its rifled barrel slides forward to load, much like the slide of a later semi-automatic pistol. A distinctive feature was a removable auxiliary steel chamber fitted with a percussion nipple, allowing the owner to fire loose powder and ball with a percussion cap when metallic .41 rimfire cartridges were unavailable.

Specifications

Weight (empty)227 g (8.0 oz)
Weight (loaded)236 g (8.3 oz)
Overall Length127 mm (5.00")
Barrel Length64 mm (2.52")
Height70 mm (2.76")
Width22 mm (0.87")
Action TypeBreech Loading
Firing MechanismSingle Action
Trigger TypeSingle Action
Magazine Capacity1 rounds
Muzzle Velocity130 m/s (427 fps)
Muzzle Energy71 J (52 ft·lbf)
Effective Range7 m (8 yd)
Maximum Range70 m (77 yd)
Barrel RiflingRight Hand
Frame MaterialBrass
Barrel MaterialSteel
Stock MaterialWalnut
FinishBlued

Calibers

Features

Service history

Operators

Production

Production years: 1866-1870

Produced for roughly four years by Moore's Patent Firearms Co. and the National Firearms Co. of Brooklyn, New York.

Origin

Country of origin: United States

Designer: David Williamson

Discontinued: 1870

Notes

Engraved on the barrel with "Williamson's Patent October 2. 1866 New York." The dual rimfire/percussion capability was a practical hedge during the transition from cap-and-ball to self-contained cartridge ammunition.

Background

Marketed as a gentleman's pocket pistol during the post-Civil War era, the Williamson's clever auxiliary percussion chamber let a frontier owner keep the gun in service even when factory .41 rimfire rounds ran short, simply by loading loose powder, ball, and a percussion cap.