Allen's Side-Swing Pistols and Derringers
Commercial era:
Allen & Wheelock
E.Allen & Co
Related patents:
Side-swing, single-shot pistols and derringers are simple pocket firearms in which the barrel pivots to the side for loading and unloading. They are typically constructed with a steel frame and barrel. A variety of barrel profiles were used, though most are either fully octagonal or half-octagonal/half-round, with lengths varying by model.
Production of the side-swing pistols began around 1861 and continued through the end of the E. Allen & Co period.
Interestingly, Ethan Allen patented the case ejector for these side-swing pistols in March 1865 (U.S. Patent No. 46,617). However, this ejector system had already been in use for several years prior to the patent. This explains why pistols from the Allen & Wheelock period lack patent markings, while those produced under E. Allen & Co include the patent date on the barrel.
Although the later models are essentially identical in design, they are commonly referred to as derringers due to their predominantly short barrel lengths and the adoption of a bird’s-head grip shape.
Pistols:
The pistol variants were produced in .22 RF and .32 RF calibers, each with multiple configurations:
- Case ejector: On the .32 models, the ejector was introduced very early in production, with only a few initial examples lacking it. On the .22 models, however, the ejector was not introduced until the E. Allen & Co period.
- The barrel: Both .22 and .32 models have been produced with fully octagonal and half-octagonal / half-round barrels. The barrel lengths can vary from 2″ to 5.5″ for the .22 models and from 3″ to 6″ for the .32 models.
- Barrel overlap (lip): Found only on .32 models, three frame variations exist: 1) without barrel overlap; 2) with short barrel overlap; 3) with long barrel overlap. The barrel overlap undoubtedly makes the pistol more robust, but was apparently not necessary since on later models this overlap disappears.
- Frame & Grip: Models from the Allen & Wheelock period have a rounded frame and grip, whereas E. Allen & Co pistols typically have a flattened frame and a grip styled after Smith & Wesson designs.
Derringers:
The derringers represent a continuation of the side-swing, single-shot line of pistols. Compared to their predecessors, they feature a more streamlined frame and a distinctive bird’s-head grip.
With a few noted exceptions, most derringers are built with a steel frame, a half-round/half-octagonal barrel, and include a case ejector. Barrel lengths vary depending on the specific model.
These derringers were produced throughout the entire E. Allen period and are typically marked:
E. ALLEN & CO WORCESTER MASS. / ALLEN’S PAT. MCH. 7, 1865
Exceptions to general rules:
- A few specimens of the .32rf derringer have been observed with a brass frame.
- The .41rf derringer has also been produced in limited quantities with a full octagonal barrel.
- Engraved or highly embellished derringers are quite rare, but examples do exist—such as this particularly fine specimen featuring ivory grips
In addition, a tiny Vest Pocket derringer, one of the smallest 22rf pistols ever produced, was introduced in 1869. This model has a bras frame, lacks a case ejector and is marked E.ALLEN & CO MAKERS.
Allen & Wheelock Side-Swing Pistol with long barrel-overlap - 32RF
This is a nickel-plated version with a fully octagonal barrel and a large barrel-overlap. It has the typical rounded grip and round frame shape from the Allen & Wheelock period.
Estimated production falls between 500 and 1,000 pieces.
Although equipped with a case ejector, this pistol lacks the patent date in its barrel markings.
Allen & Wheelock Side-Swing Pistol - round barrel - short overlap
This is a standard 32RF blued example having a half-octagonal, half-round barrel with the short barrel-overlap. Like the model above, it displays the characteristic rounded grip and rounded frame typical of the Allen & Wheelock period.
The total production, encompassing all variants, is estimated to be approximately 1000 units.
Aside from its assembly number, this specimen bears no markings.
Note the right grip plate features four carved recesses. Their exact significance remains open to interpretation.
Allen & Wheelock Side-Swing Pistol - Octagonal barrel - short overlap
This is another variant of the 32RF short barrel-overlap type, having a full octagonal barrel. Like the model above, the pistol hasn’t any markings besides the assembly number, but bears all the characteristics of the side-swing pistols of the Allen & Wheelock era.
E. Allen & Co Side-Swing Pistol - 32RF
Models from the E. Allen period are by far the most commonly encountered. They share consistent features, including a half-octagonal, half-round barrel without barrel overlap. These pistols typically have a Smith & Wesson style grip and a flattened frame profile.
Total production is estimated to be in the several thousands.
E. Allen & Co Makers Vest Pocket Derringer - 22RF
A beautifully crafted miniature side-swing derringer in excellent condition, this example is among the smallest .22 RF derringers ever produced. Measuring just under 4″ in overall length and weighing less than 100 grams, it was designed as an ultra-compact “vest pocket” pistol.
Production was limited to a short period from 1869 to 1871, resulting in relatively few surviving examples—especially in such well-preserved condition.
Unlike its larger counterparts from the same era, this Vest Pocket model lacks a case ejector and features a distinct barrel marking, further setting it apart.
E. Allen & Co Derringer - 32RF
This model was produced in both blued and nickel-plated finishes, with barrel lengths of 2″, 3.5″, 4″, and the much scarcer 6″ variant. All examples feature a distinctive barrel profile that is half octagonal and half round.
Among derringers, the .32 caliber version is the rarest, with total production estimated at fewer than 1,500 units.
E. Allen & Co Derringer - 41RF - Round barrel
This model was produced in both blued and nickel-plated finishes, with short barrels measuring from 2.5″ to 2-7/8″, and was offered in either round or octagonal barrel configurations. The round-barrel variant, as seen here, is the most commonly encountered.
Total production of these .41 RF derringers is estimated to be fewer than 2,000 units.
This particular example was imported into the UK and bears Birmingham proof marks on the barrel, adding to its historical interest.
E. Allen & Co Derringer - 41RF - Octagonal barrel
This model was produced in both blued and nickel-plated finishes, with short barrels measuring between 2.5″ and 2-7/8″. It was offered in either round or octagonal barrel configurations. This particular example—featuring nickel plating and an octagonal barrel—remains in excellent condition and is exceptionally rare.
From the P.O. collection
