Revolver

.357 Magnum Ruger Vaquero single-action revolver; modeled after the Colt Single Action Army

A revolver is a repeating firearm that has a cylinder containing multiple chambers and at least one barrel for firing. As the user cocks the hammer, the cylinder revolves to align the next chamber and round with the hammer and barrel, which gives this type of firearm its name. In modern revolvers, the revolving cylinder typically chambers 5 or 6 rounds, but some models hold 10 rounds or more. Revolvers are most often handguns, but other weapons may also have the design of a revolver. These include some models of grenade launchers, shotguns, and some rifles.

Design

Details of a Schmidt M1882, showing the hammer, chambers for the ammunition in the cylinder, and the mechanism to rotate the cylinder. Revolver of the Gendarmerie of Vaud, on display at Morges castle museum.

A revolver works by having several firing chambers arranged in a circle in a cylindrical block that are brought into alignment with the firing mechanism and barrel one at a time. In contrast, other repeating firearms, such as lever-action, pump-action, and semi-automatic, have a single firing chamber and a mechanism to load and extract cartridges into it.

A single-action revolver requires the hammer to be pulled back by hand before each shot, which also revolves the cylinder. This leaves the trigger with just one "single action" left to perform - releasing the hammer to fire the shot - so the force and distance required to pull the trigger can be minimal. In contrast, with a self-cocking revolver, one long squeeze of the trigger pulls back the hammer and revolves the cylinder then finally fires the shot. They can generally be fired faster than a single-action, but at the cost of reduced accuracy in the hands of most shooters.

Most modern revolvers are "traditional double-action", which means they are able to operate either in single-action or self-cocking mode. The accepted meaning of "double-action" has, confusingly, come to be the same as "self-cocking", so modern revolvers that cannot be pre-cocked are called "double-action-only". These are intended for concealed carry, because the hammer of a traditional design is prone to snagging on clothes when drawn.

Most commonly, such guns have a 5- or 6-shot capacity, hence the common names of "six-gun" or "six-shooter". However, some revolvers have a 7- to 10-shot capacity, often depending on the caliber. Each chamber has to be reloaded manually, which makes reloading a revolver a much slower procedure than reloading a semi-automatic pistol.

The alternatives are a replaceable cylinder, a speedloader, which can reload all chambers at once, or a moon clip that holds a full load (or even half of one in the case of a half-moon clip) of ammunition and that is inserted along with the ammunition. In revolvers chambered for rimless cartridges, moon clips are normally required. Another product known as a "speedstrip" cannot reload a completely empty revolver as rapidly as a speedloader, but is less expensive, flatter, and more flexible when it comes to partial reloads.

Compared to autoloading handguns, a revolver is often simpler to operate (despite often being more mechanically complex) and may have greater reliability (depending on factors such as firmness of grip, ammunition or cartridge used, and degree of maintenance and lubrication provided to the firearm). For example, should a semiautomatic pistol fail to fire, clearing the chamber requires manually cycling the action to remove the errant round, as cycling the action normally depends on the energy of a cartridge firing. With a revolver, this is not necessary as none of the energy for cycling the revolver comes from the firing of the cartridge, but is supplied by the user either through cocking the hammer or, in a double action design, by just squeezing the trigger. Another significant advantage of revolvers is superior ergonomics, particularly for users with small hands. A revolver's grip is not required to accommodate a magazine, and it can be designed or customized much more than a typical semi-automatic.

In general, revolvers stand up to long-term neglect better than semi-automatics, an example of neglect being the common scenario of a civilian who keeps a weapon for defense but rarely shoots or maintains it. A revolver can be kept loaded and ready to fire without compressing any springs (which weaken over time with continual load) and is not very dependent on lubrication for proper firing. However, a revolver is generally not as resistant to abuse as a semi-automatic (abuse meaning dropping the weapon, or allowing severe contamination by dirt or mud). The revolver's clockwork-like internal parts are relatively delicate and can become misaligned after a severe impact, and its revolving cylinder can become jammed by excessive dirt or debris. The latter factors are more of a concern for military users than civilians or police.

Over the long period of development of the revolver, many calibers have been used. Some of these have proved more durable during periods of standardization and some have entered general public awareness. Among these are the .22 rimfire, a caliber popular for target shooting and teaching novice shooters; .38 Special and .357 Magnum, known for its police use; the .44 Magnum, famous from Clint Eastwood's "Dirty Harry" films; and the .45 Colt, used in the Colt revolver of the Wild West. Introduced in 2003, the Smith & Wesson Model 500 is the most powerful production revolver ever created, using the .500 S&W Magnum round.

The LeMat Revolver, an unusual revolver from the American Civil War era with 9 revolving chambers firing bullets and a center shotgun barrel firing lead shot.

Revolvers have been largely replaced by semi-automatic pistols in military and law enforcement applications. Their lower ammunition capacities and relatively longer reload times compared to autoloading pistols are the main reasons for the switchover, which occurred over the first half of the century for military applications, and in the 1980s and 1990s for police forces. Additionally, the flat profile of semi-automatics make them more suitable for concealed carry. Revolvers still remain popular in the role of back-up and off-duty guns among American law enforcement officers and security guards. Also, revolvers are still common in the American private sector as defensive and sporting/hunting firearms. Famous police and military revolvers include the Webley, the Colt Single Action Army, the Smith & Wesson Model 29, the Smith & Wesson Model 10, and the Smith & Wesson 1917.

Revolver technology does live on in other weapons used by the military. Some autocannons and grenade launchers use mechanisms similar to revolvers, and some riot shotguns use spring loaded cylinders holding up to 12 rounds. In addition to serving as backup guns, revolvers still fill the specialized niche role as a shield gun; law enforcement personnel using a "bulletproof" ballistic shield (Gun shield) sometimes opt for a revolver instead of a self-loading pistol, because the slide of a pistol may strike the front of the shield when fired. Revolvers do not suffer from this disadvantage. A second revolver may be secured behind the shield to provide a quick means of continuity of fire. Many police also still use revolvers as their duty weapon due to their relative mechanical simplicity and user friendliness.^[1]

With the advancement of technology and design in 2010 major revolver manufacturers are coming out with polymer frame revolvers like the Ruger LCR, Smith & Wesson Bodyguard 38, and Taurus Protector Polymer. The new innovative design incorporates advanced polymer technology that lowers weight significantly, helps absorbs recoil, and strong enough to handle +P and .357 Magnum loads. The polymer is only used on the lower frame and joined to a metal alloy upper frame, barrel, and cylinder. Polymer Revolver technology is considered one of the major advancements in revolver history because the frame has always been metal alloy and mostly one piece frame design.

Loading and unloading

Front loading

Army 1860 with fluted Cylinder and 7.5-inch barrel serial No. 1158

The first revolvers were front loading, and were a bit like muskets in that the powder and bullet were loaded separately. These were caplocks or "cap and ball" revolvers, because the caplock method of priming was the first to be compact enough to make a practical revolver feasible. When loading, each chamber in the cylinder was rotated out of line with the barrel, and charged from the front with loose powder and an oversized bullet. Next, the chamber was aligned with the ramming lever underneath the barrel. Pulling the lever would drive a rammer into the chamber, which sealed it and held the ball and powder securely in place. Finally, the user would place percussion caps on the nipples on the rear face of the cylinder.

Loading a cylinder was a slow and awkward process, so soldiers in the field often carried multiple revolvers. Some models had removable cylinders that could be swapped out.

After each shot, a user was advised to raise his revolver vertically while cocking back the hammer so as to allow the fragments of the spent percussion cap to fall out safely. Otherwise, the fragments could fall into the revolver's mechanism and jam it.^[2] Caplock revolvers were also vulnerable to "chain fires", wherein hot gas from a shot ignited the powder in the other chambers. This could be prevented by sealing the chambers with cotton or grease.

Fixed cylinder designs

A fixed-cylinder Nagant M1895 with gate open for loading

In many of the first generation of cartridge revolvers (especially those that were converted after manufacture), the pin on which the cylinder revolved was removed, and the cylinder taken from the gun for loading. Later models used a loading gate at the rear of the cylinder that allowed one cartridge at a time to be accessed for loading, while a rod under the barrel could be pressed backwards to extract the fired case. Most revolvers using this method of loading are single-action revolvers, although Iver Johnson produced double-action models with removable cylinders. The removable-cylinder design is employed in some modern "micro-revolvers" (usually in .22 caliber), in order to simplify their design. These weapons are small enough to fit in the palm of the hand.

The loading gate on the original Colt designs (and on nearly all single-action revolvers since, such as the famous Colt Single Action Army) is on the right side, which may favor left-handed users; with the revolver held in the proper grip for shooting in the left hand, the cartridges can easily be ejected and loaded with the right.^[3]

Since the cylinder in these revolvers is firmly attached at the front and rear of the frame, and since the frame is typically full thickness all the way around, fixed cylinder revolvers are inherently strong designs. Because of this, many modern large caliber hunting revolvers tend to be based on the fixed cylinder design. Fixed cylinder revolvers can fire the strongest and most powerful cartridges, but at the price of being the slowest to load and cannot use speedloaders or moon clips for loading as one chamber is exposed at a time to the loading gate.

Top break

An IOF .32 top-break revolver

The next method used for loading and unloading cartridge revolvers was the top break design. In a top-break revolver, the frame is hinged at the bottom front of the cylinder. Releasing the lock and pushing the barrel down exposes the rear face of the cylinder. In most top-break revolvers, this act also operates an extractor that pushes the cartridges in the chambers back far enough that they will fall free, or can be removed easily. Fresh rounds are then inserted into the cylinder. The barrel and cylinder are then rotated back and locked in place, and the revolver is ready to fire.

Top break revolvers can be loaded more rapidly than fixed-frame revolvers, especially with the aid of a speedloader or moon clip. However, this design is much weaker and cannot handle high pressure rounds. This design is obsolete today, supplanted by the stronger yet equally convenient swing-out design.

Swing out cylinder

A swing-out cylinder revolver.

The last and most modern method of loading and unloading is the swing out cylinder. The cylinder is mounted on a pivot that is coaxial with the chambers, and the cylinder swings out and down (to the left in most cases). An extractor is fitted, operated by a rod projecting from the front of the cylinder assembly. When pressed, it will push all fired rounds free simultaneously (as in top break models, the travel is designed to not completely extract longer, unfired rounds). The cylinder may then be loaded, singly or again with a speedloader, closed, and latched in place.

The pivoting part that supports the cylinder is called the crane; it is the weak point of swing-out cylinder designs. Using the method often portrayed in movies and television of flipping the cylinder open and closed with a flick of the wrist can in fact cause the crane to bend over time, throwing the cylinder out of alignment with the barrel. Lack of alignment between chamber and barrel is a dangerous condition, as it can impede the bullet's transition from chamber to barrel. This gives rise to higher pressures in the chamber, bullet damage, and the potential for an explosion if the bullet becomes stuck.

The shock of firing can also put a great deal of stress on the crane, as in most designs the cylinder is only held closed at one point, the rear of the cylinder. Stronger designs, such as the Ruger Super Redhawk, use a lock in the crane as well as the lock at the rear of the cylinder. This latch provides a more secure bond between cylinder and frame, and allows the use of larger, more powerful cartridges. Swing out cylinders are rather strong, but not as strong as fixed cylinders, and great care must be taken with the cylinder when loading, so as not to damage the crane.

Action

Single-action

USFA US Pre-War Single Action Army at full-cock, ready to fire

In a single-action revolver, the hammer is manually cocked, usually with the thumb of the firing or supporting hand. This action advances the cylinder to the next round and locks the cylinder in place with the chamber aligned with the barrel. The trigger, when pulled, releases the hammer, which fires the round in the chamber. To fire again, the hammer must be manually cocked again. This is called "single-action" because the trigger only performs a single action, of releasing the hammer. Because only a single action is performed and trigger pull is lightened, firing a revolver in this way allows most shooters to achieve greater accuracy. Additionally, the need to cock the hammer manually acts as a safety.

Double-action

Colt Anaconda .44 Magnum double-action revolver

In double-action (DA), the stroke of the trigger pull generates two actions: (1) the hammer is pulled back to the cocked position while the cylinder is being indexed to the next round, and then (2) the hammer is released to strike the firing pin. Thus DA means that a cocking action separate from the trigger pull is unnecessary; and every trigger pull will result in a complete cycle. This allows uncocked carry while also allowing draw-and-fire using only the trigger. A longer and harder trigger stroke is the trade-off, but this con can also be viewed as a pro (more drop-safe).

Most double-action revolvers may be fired in two ways.

The first way is single-action, that is, exactly the same as a single-action revolver; the hammer is cocked with the thumb, which indexes the cylinder, and when the trigger is pulled, the hammer is tripped.
The second way is double action, that is, from a hammer-down position. In this case, the trigger first cocks the hammer and revolves the cylinder, and then trips the hammer at the rear of the trigger stroke, firing the round in the chamber.

Enfield No. 2 Mk I* double-action-only revolver. Note the spurless hammer.

Certain revolvers, called double action only (DAO), lack the latch that enables the hammer to be locked to the rear, and thus can only be fired in the double action mode. With no way to lock the hammer back, DAO designs tend to have bobbed or spurless hammers, and may even have the hammer completely covered by the revolver's frame (i.e., shrouded or hooded). These are generally intended for concealed carrying, where a hammer spur could snag when the revolver is drawn. The potential reduction in accuracy in aimed fire is offset by the increased capability for concealment.

DA and DAO revolvers were the standard-issue sidearm of countless police departments for many decades. Only in the 1990s did the semiautomatic pistol begin to make serious inroads, after the advent of safe actions such as Glock's. The reasons for these choices are the modes of carry and use. Double action is good for high-stress situations because it allows a mode of carry in which "draw and pull the trigger" is the only requirement—no safety catch release or separate cocking stroke required. Although those seem simple to a person in calm circumstances, it is considered that less can go wrong with a simpler action when the user is highly stressed. This is a school of thought, not an immutable rule; some users would not make the same choice (preferring, e.g., cocked-and-locked carry), although they understand the logic.

Other

In the cap-and-ball days of the mid nineteenth century, two revolver models, the English Tranter and the American Savage “Figure Eight”, used a method whereby the hammer was cocked by the shooter’s middle finger pulling on a second trigger below the main trigger.

Iver Johnson made an unusual model from 1940 to 1947, called the Trigger Cocking Double Action. If the hammer was down, pulling the trigger would cock the hammer. If the trigger was pulled with the hammer cocked, it would then fire. This meant that to fire the revolver from a hammer down state, the trigger must be pulled twice.^[4]

Use with suppressors

As a general rule, revolvers cannot be equipped with a sound suppressor ("silencer"), as there is usually a small gap between the revolving cylinder and the barrel which a bullet must traverse or jump when fired. From this opening, a rather loud report is produced even when a suppressor is installed on the end of the barrel of most revolvers.

A suppressible revolver design does exist in the Nagant M1895, a Russian military revolver used from 1895 through World War II. This revolver uses a unique cartridge that extends beyond the tip of the bullet, and a cylinder that moves forward to place the end of the cartridge inside the barrel when ready to fire. This bridges the gap between the cylinder and the barrel, and expands to seal the gap when fired. While the tiny gap between cylinder and barrel on most revolvers is insignificant to the internal ballistics, the seal is especially effective when used with a suppressor, and a number of suppressed Nagant revolvers have been used since its invention.^[5]

There is a modern revolver of Russian design, the OTs-38,^[6] which uses ammunition that incorporates the silencing mechanism into the cartridge case, making the gap between cylinder and barrel irrelevant as far the suppression issue is concerned. The OTs-38 does need an unusually close and precise fit between the cylinder and barrel due to the shape of bullet in the special ammunition (Soviet SP-4), which was originally designed for use in a semi-automatic.

Additionally, the US Military experimented with designing a special version of the Smith and Wesson Model 29 for Tunnel Rats, called the Quiet Special Purpose Revolver or QSPR. Using special .40 caliber ammunition, it never entered service, at least officially.^[7]

Automatic revolvers

Webley-Fosbery Automatic Revolver.

Double action revolvers use a long trigger pull to cock the hammer, thus negating the need to manually cock the hammer between shots. The disadvantage of this is the long, heavy pull that cocks the hammer makes the double action revolver much harder to shoot accurately than a single-action revolver (although cocking the hammer of a double action reduces the length and weight of the trigger pull). There is a rare class of revolvers, the automatic revolver, that attempts to overcome this restriction, giving the high speed of a double action with the trigger effort of a single-action.

The Webley-Fosbery Automatic Revolver was the first commercial example, introduced in 1901. It was recoil-operated, and the cylinder and barrel recoiled backwards to cock the hammer and revolve the cylinder. It was distinctive in that cam grooves were milled on the outside of the cylinder to provide a means of advancing to the next chamber—half a turn as the cylinder moved back, and half a turn as it moved forward. .38 caliber versions held 8 shots, .455 caliber versions 6. At the time, the few available automatic pistols were larger, less reliable, and more expensive. The automatic revolver was popular when it first came out, but was quickly superseded by the creation of reliable, inexpensive semi-automatic pistols.

In 1997, the Mateba company developed a type of recoil-operated automatic revolver, commercially named the Mateba Autorevolver, which uses the recoil energy to auto-rotate a normal revolver cylinder holding 6 or 7 cartridges, depending on the model. The company has made several versions of its Autorevolver, including longer barrelled and carbine variations, chambered for .357 Magnum, .44 Magnum and .454 Casull. The Pancor Jackhammer is a combat shotgun based on a similar mechanism to an automatic revolver. It uses a Blow-Forward action to move the barrel forward (which unlocks it from the cylinder) and then rotate the cylinder and cock the hammer. The Pancor Jackhammer is an example of a Machine Revolver.

Six gun

A Six Gun is a revolver that holds six bullets. The cylinder in a six gun is often called a 'wheel', and the six gun is itself often called a 'wheel gun'. The classic six gun was commonly carried by Old West cowboys and gunfighters. A well-known example of the six gun is the Colt Single Action Army, or Peacemaker, in .45 Long Colt caliber. The six gun has many modern incarnations, such as the Ruger Vaquero and Beretta Stampede, as well as the currently produced Colt Single Action Army.

The basic operation of the six gun is:

The hammer is cocked with the thumb, which rotates the cylinder to line up a new cartridge with the barrel, and positions the hammer for firing.
The trigger is pulled, which causes the hammer to drop and sharply push the firing pin into the cartridge primer, firing the gun.
The hammer must be cocked again for the next shot. This is called 'Single-Action'.

Modern six guns are used commonly by Single-Action Shooting enthusiasts in shooting competitions, designed to mimic the gunfights of the Old West, and for general target shooting and personal defense.^[8]

History

6-chambered wheel-lock revolver (Germany 1590)

In the development of firearms, an important limiting factor was the time it took to reload the weapon after it was fired. While the user was reloading, the weapon was nearly useless, and an adversary might be able to take advantage of the situation and kill or wound the user. Several approaches to the problem of increasing the rate of fire were developed, the earliest being multi-barreled weapons which allowed two or more shots without reloading. The first revolvers were partly an attempt to improve on pepper-box type weapons, which used a revolving cylinder with one set of firing mechanisms, but which had multiple barrels as well. Firing through a single barrel saved the expense and weight of having the multiple barrels of the pepper-box.

The earliest example of a revolver is a revolving arquebus, produced by Hans Stopler in 1597.^[9] Another early specimen, now in the Tower of London armories, is dated to the middle 1600s and attributed to John Dafte of London. This example, a flintlock, uses a single lock, with a flash pan for each of the six chambers. The cylinder is rotated by hand, and locks in place for firing. This was still not perfected, however, as it was apparently destroyed by a misfire.^[10]

James Puckle patented a revolving chamber gun in 1718. This gun, which had a 1.25 inch bore (30 mm), was tripod mounted, and the 11-shot cylinder was operated by a hand crank. It is often cited as the first machine gun. By changing cylinders to reload (an early example of a speedloader), the gun was fired and reloaded to fire a total of 63 rounds in seven minutes. Elisha Collier patented a flintlock revolver in Britain in 1818, and significant numbers were being produced in London by 1822.

The revolver mechanism was sometimes used in rifle design. The difficulty of this approach is that the hot gas that leaks from the gap between the chamber and barrel can burn the user's forward hand.

In 1836, Samuel Colt patented a revolver mechanism that led to the widespread use of the revolver. According to Samuel Colt, he came up with the idea for the revolver while at sea, inspired by the capstan winch, which had a ratchet and pawl mechanism on it, a version of which was used in his guns to rotate the cylinder. Revolvers proliferated largely due to Colt's ability as a salesman.

Early revolvers were caplocks and loaded a bit like muskets: the user poured powder into a chamber, rammed down a bullet, then placed percussion caps between the hammer and cylinder. After firing a shot, the user would raise his pistol vertically as he cocked the hammer back so as to let the fragments of the percussion cap fall out and not jam the mechanism.

Revolvers have remained popular to the present day in many areas, although in the military and law enforcement they have largely been supplanted by magazine-fed semi-automatic pistols such as the Colt M1911, especially in circumstances where reload time and higher cartridge capacity are deemed important.

Patents

Elisha Collier patented a flintlock revolver in Britain in 1818, and significant numbers were being produced in London by 1822. The origination of this invention is in doubt, as similar designs were patented in the same year by Artemus Wheeler in the United States and by Cornelius Coolidge in France. Samuel Colt received a British patent for his revolver in 1835 and an American patent (number 138) on February 25, 1836 for a Revolving gun, and made the first production model on March 5 of that year.

Another revolver patent was issued to Samuel Colt on August 29, 1839. The February 25, 1836 patent was then reissued as U.S. Patent RE00,124 entitled Revolving gun to Samuel Colt on October 24, 1848. This was followed by U.S. Patent 0,007,613 on September 3, 1850 for a Revolver, and by U.S. Patent 0,007,629 on September 10, 1850 for a Revolver. U.S. Patent 5,333,531 was issued to Roger C. Field for an economical device for minimizing the flash gap of a revolver between the barrel and the cylinder. In 1855, Rollin White patented the bored-through cylinder entitled Improvement in revolving fire-arms U.S. Patent 00,093,653. In 1856 Horace Smith & Daniel Wesson formed a partnership (S&W), developed and manufactured a revolver chambered for a self-contained metallic cartridge.

Notable brands and manufacturers

Robert Adams
Armscor
Astra
Charter Arms
Colt's Manufacturing Company
Royal Small Arms Factory
Fabrique Nationale de Herstal
Harrington & Richardson
Iver Johnson
Magnum Research

Mateba Arms
Nagant
North American Arms
Remington Arms
Sturm, Ruger & Company
Smith & Wesson
Taurus Firearms
United States Fire-Arms Manufacturing Company
William Tranter
Webley & Scott

Gallery

Mateba Autorevolver	Colt Anaconda .44 Magnum revolver	Colt New Service revolver	Colt Python .357 Magnum revolvers
Smith & Wesson Model 686 .357 Magnum revolvers	Smith & Wesson Model 625 for IPSC shooting	Taurus .357 Magnum Model 605	Taurus .45 Long Colt/.410 bore Model 4510 'The Judge'
Webley Mk IV in .380 S&W	IOF .32 Revolver in .32 S&W	Belgian-made Lefaucheur revolver, circa 1860-1865	A Russian Nagant M1895 on display.