The 19th century saw a surge in arms innovation, including the introduction and development of the single action and double action revolver. Both platforms competed head-to-head in the civilian and military markets, with Europe and America taking two different directions early on.

It's a single action vs double action shodown this October at RIAC! (Top) A James M. Stanley signed and game scene engraved S&W Model 629 with case. (Bottom) A factory engraved Colt SAA with a relief carved ox head grip.

We'll explore the single action vs double action faceoff through the decades and look at some of the notable, rare, and intriguing examples in each firearm platform found at Rock Island Auction Company. Click on the images throughout this article to learn more about each model.

Single Action Vs Double Action Revolvers

Single action systems require two steps. The action must be manually cocked and pulling the trigger fires the weapon. In a double action system, both functions are accomplished in a single step, allowing a shooter to put lead downrange as fast as they can pull the trigger.

An antique black powder frame Colt SAA, an example of the most famous single action model in history.

In the single action vs double action showdown, the double action platform carries a number of key advantages. Double action offers a more rapid firing rate. The heavier double action trigger pull also reduces the chance of an accidental discharge, an important safety consideration in an everyday carry sidearm meant for self-defense.

Fewer motions are needed to operate a double action, a useful feature for those with movement restrictions or anyone in a high stress scenario. Not being required to cock the hammer before each shot also allows a double action revolver to be fired from a coat pocket with less manipulation. Without the need for a spurred hammer, the double action also offers less risk of snagging clothing when drawn.

A cased Smith & Wesson Model 27-5 double action revolver with an engraved silver plated cylinder.

In the single action's favor, the system usually offer a lighter trigger pull. Single action firearms typically employ simpler internals, which sometimes translates to lower production costs. Less bulky internals also make single action mechanisms ideal for small derringers and novelty weapons like pen guns, knife guns, and credit card guns.

Single action revolvers offer a unique shooting experience and for some shooters have a more natural point and feel. And few firearm fans would deny that classic single action wheelguns like the Colt SAA have fantastic lines and curves.

A Colt Model 1871-1872 Open Top single action revolver, an example of the first non-conversion Colt cartridge wheelgun.

The double action/single action system found on many curio and modern revolvers combines some of the advantages of both platforms: the rapidity of the double action and the light trigger and precision of the single action.

Upgraded Smith & Wesson Military & Police Model 1905 First Change DA revolvers with ivory grips.

Birth of the Single Action Percussion Revolver

Revolving firearms have been around since the 16th century, with most matchlock and flintlock designs requiring the shooter to manually rotate the cylinder after each shot. In 1836, Samuel Colt was the first to patent a system that accurately synced a rotating cylinder to a fixed barrel.

A cased Patent Arms Manufacturing Company "Colt Baby Paterson" No.1 Pocket model percussion revolver with a full set of accessories.

The Paterson set the stage for Colt single action revolvers to dominate the American market. A host of revolver designs were developed by competitors hoping to circumvent Samuel Colt’s patents, but the Connecticut gun mogul's most serious early competitor would arise across the pond in the form of a double action design.

An exceptional documented cased early factory "donut scroll" engraved presentation Colt Model 1849 pocket percussion single action revolver featured in "The Colt Engraving Book Vol. 1."

Birth of the Double Action Percussion Revolver

In 1851, Robert Adams patented a double action revolver system that could index the cylinder as well as cock and drop the hammer with a single trigger pull. Adams’ initial design, dubbed a "self-cocking revolver," was a double action only with the hammer spur removed so it could not be manually cocked.

A cased pair of Williams & Powell retailer marked London Armoury Company Beaumont-Adams double action revolvers, identified as owned by Governor Rufus Bullock of Georgia.

Adams and Colt both displayed their guns in London at the Crystal Palace Exhibition of 1851, the first time the single action and double action revolvers were seriously compared on the world stage. The exhibition immediately popularized the Adams design and set off a spirited debate in the British media about which revolver mechanism was superior.

A rare factory engraved Colt Hartford English Dragoon percussion revolver, one of only approximately 700 manufactured in London between 1853 and 1857.

Single vs Double Action Percussion Revolvers in the Field

The single action vs double action design competed head-to-head in October of 1851, when the British Committee on Small Arms tested the Adams revolver and the Colt Model 1851 Navy at Woolwich. In the two hour trials, the Adams fired 25 times with no misfires, while the Colt suffered four. The Adams was chambered for a larger .44 cartridge, offered a smooth and robust action, and could fire more rapidly.

A historic presentation cased Gustave Young factory engraved Colt Model 1851 Navy percussion revolver with Civil War Philadelphia National Guard Officer's inscription.

Noted drawbacks for the Adams included its lack of loading lever and its longer double action only trigger pull hindering the gun's accuracy. The Adams had more parts than the Colt single action designs and relied more on hand craftsmanship than the machine assisted manufacturing processes Colt had pioneered, which resulted in a higher price point and slower production time.

A cased Tranter Patent double action revolver, an evolution of the Adams design.

Robert Adams and his partners immediately worked to improve the design, including the addition of a bullet rammer similar to one in use by W. & J. Rigby. Pocket, holster, and belt models were offered in a variety of chamberings. Commercial sales were promising, and the Deane, Adams & Deane double action revolver became a popular option for British officers during the Crimean War of 1853 and the Indian Rebellion of 1857.

The Crimean War became the first major military proving ground in the single action vs double action arms race. A letter from Crimean War soldier J. G. Crosse from the 88th Regiment of Foot to Robert Adams illustrates a growing sentiment among the British military.

"I had one of your largest sized Revolver Pistols at the bloody battle of Inkermann, and by some chance got surrounded by the Russians. I then found the advantages of your pistol over that of Colonel Colt’s, for had I to cock before each shot I should have lost my life. I should not have had time to cock, as they were too close to me, being only a few yards from me; so close that I was bayoneted through the thigh immediately after shooting the fourth man."

An Adams Patent Tipping & Lawden Hammer Safety double action revolver with case.

An improved bullet rammer designed by Adam's cousin James Kerr was incorporated, and after the Crimean War the Adams revolver added a hammer spur and a single action/double action lock that had been patented by Lieutenant Frederick E. B. Beaumont. The Beaumont-Adams revolvers became a British army standard for the next 24 years. The platform saw numerous variants and clones and steered the European market toward double action revolvers over their single action competitors.

A cased London Armoury Co. Beaumont-Adams double action percussion revolver, a successor to the original Adams design.

Single Action vs Double Action in America

Though European competition forced Samuel Colt to close his London factory in 1856, his single action revolvers continued to rule the American market. Meanwhile, numerous double action revolvers were produced by American manufacturers in the 1850s, including examples by Cooper Firearms, Starr Arms, and Rodgers & Spencer & Co. The latter company manufactured the Pettengill, the Civil War's only hammerless revolver model. In 1863, the Remington-Rider revolver was introduced.

A Civil War U.S. contract Starr Arms Co. Model 1858 Army double action revolver.

In the midst of Colt's dominance, Smith & Wesson's evolving line of single action revolvers gained popularity with civilians, law enforcement, and militia, and eventually the company garnered some lucrative military contracts as well. To the American military, durability in the field became the most important factor when adopting a metallic cartridge revolver, and the Colt Single Action Army was viewed as an ideal frontier sidearm.

On the double action revolver, Col. James Gilchrist Benton, Springfield Armory commander from 1866 to 1881, wrote, "The only advantage this system possesses is, that the arm can be fired rapidly without disturbing the aim. The disadvantages are, liability to accidental discharge, and failure to explode the cartridge."

A U.S. Ainsworth inspected Lot 5 Colt Cavalry Model Single Action Army revolver with a John Kopec Letter.

Samuel Colt had a strong opinion on the single action vs double action debate, believing the double action platform was less accurate, more prone to mechanical failure, and wasted ammunition. This philosophy would continue to guide the company for years after Colt's passing.

In 1874, Frederick van Oppen, manager of Colt’s London Agency, sent examples of the latest Adams, Webley, and Tranter double action revolvers to his higher ups in Connecticut, writing, "All gunmakers abroad and at home, within British Dominions especially, state they can scarcely sell anything now in revolvers but double action central fire .450 bore pistols, with short to medium length barrels in preference."

Colt was slow to respond, but finally directed superintendent William Mason to develop a double action design in 1876. The Colt "Double Action, Self-Cocking Central Fire Revolving Pistol" hit the market in 1877 and became an immediate hit. Nicknames emerged for each chambering, including the "Lightning" for the .38 caliber, "Thunderer," for the .41, and "Rainmaker" for the .32 variant. The .45 caliber Model 1878, Colt's first large frame double action revolver, was dubbed the "Omnipotent."

A Pinkerton Agency marked antique Colt Model 1877 Thunderer double action revolver with a factory letter, badge, and memorabilia from actor Dale Robertson.

Smith & Wesson wouldn't produce a double action revolver until early 1880. Released alongside a single action counterpart, the Smith & Wesson Model 2 double action included a number of modifications that allowed the revolver to function as a single action/double action system. The double action version outsold its single action sibling over four to one and saw nearly a million units produced across five variations between 1880 and 1913.

A cased Smith & Wesson .38 Model 2 double action Third Model revolver.

Single Action vs Double Action Arms Race

The Single Action Army remained the standard sidearm of the U.S. military for nearly two decades. The Colt SAA was finally replaced by the Colt M1892, the first widely issued double action revolver to serve America's armed forces. The platform saw numerous updates and variants during its nearly 16 year production life and served in conflicts like the Spanish American War and the Philippine Insurrection.

Serial Number 3 Colt Model 1889 Double Action revolver shipped to Samuel Colt's son and heir, Caldwell Colt. The Model 1899 design evolved into the Model 1892 and its sucessors.

As the 20th century approached, the single action vs double action showdown was far from over. The reliable and plentiful Peacemaker continued to serve on the battlefield alongside its double action counterparts, like the Colt SAA revolver pictured below documented to a member of the Rough Riders Volunteer Cavalry.

The Moro Rebellion followed the War in the Philippines, a prolonged conflict with a local tribe that lived in the southern islands who General John Pershing described as "absolutely fearless, and once committed to combat they count death as a mere incident."

The Colt M1892 .38 caliber double action revolver proved unpowered against the zealous guerilla fighters, and the U.S. military reissued the .45 caliber Colt Single Action Army. The conflict with the Moro directly influenced America's Ordnance Department to adopt the .45 caliber New Service double action revolver and to develop the .45 ACP M1911 pistol.

A U.S. Colt Artillery Model Single Action Army revolver with a John Kopec letter, documented to George Thompson of the Rough Riders 1st U.S. Volunteer Cavalry.

Colt's hefty New Service revolver enjoyed widespread success in military, law enforcement, and civilian roles. The model became popular with British officers and was fielded by Canadian troops as well, and the platform laid the groundwork for the .45 ACP M1917 double action revolver, which supplemented the M1911 pistol throughout WW1.

A Colt New Service Target double action revolver inscribed to U.S. Presidential Secretary to President Theodore Roosevelt, William Loeb Jr.

UK forces relied on double action revolvers like the Webley and the Enfield well into the 20th century. Though long-retired as a standard issue sidearm, the Colt Single Action Army continued to serve secondary units and was carried by a few officers in WW2, including General Wainwright in the Pacific and General Patton in the European theater.

The Colt SAA pictured below is one of 163 ordered by the British Purchasing Commission as an emergency replacement for small arms lost by the British Expeditionary Force during the evacuation from Dunkirk in May 1940. These "Battle of Britain" revolvers were the last Colt Single Action Armies ordered under military contract.

A documented WW2 "Battle of Britain" Colt First Generation SAA revolver, one of only 63 from the order with nickel finish and one of only 36 chambered in .38 Special.

Single Action vs Double Action By the Numbers

The double action revolver came to dominate in the 20th century, and the proof is in the production numbers. According to Smith & Wesson "over six million" Model 10 revolvers have been produced since 1899, making the platform the most popular revolver line ever produced.

A distant second for double action revolvers, over 2 million Russian Nagant M1895s were built. The Police Positive Special double action revolver became one of Colt's best selling wheelgun line with over 750,000 manufactured. The Police Positive Special's popular snub nose spinoff, the Colt Detective Special, saw a production run of over 350,000.

An engraved "W.F. & Co." marked Colt Police Positive double action revolver with pearl grips and "WF & CO EX" marked holster.

Smith & Wesson's double action N-frame revolvers became one of the most popular handgun platforms, with over 1.3 million produced including the Model 27, Model 28, and Model 29. Combined numbers for S&W I-Frame revolvers like the Model 30, 31, 32, 33, 34, and 35 aren't far behind. Colt's medium frame Official Police model, previously known as the Colt Army Special saw a production run of over 1 million units across all variations.

An engraved Smith & Wesson Pre-Model 27 .357 Magnum double action revolver with relief carved dragon grips, its case, and a factory letter.

The single action vs double action popularity contest is far from one-sided, however, and one of the biggest reasons for the continued success of the classic SA revolver has been Ruger Firearms. Introduced in 1955, the Ruger Blackhawk has become the most produced single action revolver line in history with over 2 million sold.

The Blackhawk's smaller sibling, the Single Six, holds second place among single action revolvers with over 1.5 million produced since it hit the market in 1953. The Ruger Vaquero, released in 1993, earns the third spot with over 650,000 manufactured and counting.

An engraved Ruger New Model Super Blackhawk Charleston West Virginia Commemorative single action revolver with case, one of 100 manufactured in 2014.

Single Action vs Double Action Today

The SA/DA revolver has come to fill nearly every role, particularly everyday carry and self defense, but as Ruger sales numbers demonstrate, single action continues to enjoy widespread popularity. A decade after WW2, Colt resumed production of their Single Action Army with their Second Generation run. The Golden Age of Westerns was at its height, spurring nostalgia for the Wild West and the frontier firearms featured onscreen.

An experimental prototype Colt New Frontier single action revolver in .44 Magnum, one of only 25 produced.

Ruger's Blackhawk took inspiration from a generation of custom Colt SAAs and paired the design with Remington's new .44 Magnum cartridge. In his 1955 book, 'Sixgun,' outdoor legend Elmer Keith was impressed with the Blackhawk, noting, "For the shooter, be he plinker, peace officer, cow-poke or hunter, this new Ruger is a good, well-made arm. Colt collectors may prefer the original old Peacemaker but any shooter who wants to have first class target sights combined in a really modern arm with all improvements including the rebounding separate firing pin will find the new Ruger Blackhawk the finest single action revolver manufactured to date."

A cased matching set of Heidi Roos engraved Ruger 50th Anniversary New Model Blackhawk single action revolvers.

Colt's Third Generation Single Action Army was initially offered as a limited run starting in 1976, but renewed interest in the platform prompted Colt to resume production of the classic in 1994. Thanks to firearm focused online communities, Cowboy Action Shooting, depictions in popular media, and the mainstream appeal of gun collecting, the single action revolver continues to appeal to a wide audience.

A factory engraved Colt Third Generation Single Action Army revolver with box and case.

Single Action vs Double Action Collecting

The single action vs double action debate is ultimately going to come down to individual preference and the intended role being filled. Most arms enthusiasts enjoy owning numerous guns that offer distinct and memorable shooting experiences. For handgun hunting, single action only and SA/DA revolvers are available today in almost every chambering. For the sportsman, shooter, and collector, rare and historic examples of each style can be found at Rock Island Auction Company.

A cased "U.S.EX." marked Marlin Model 1887 double action revolver.

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A rare documented antique factory engraved Colt Model 1889 DA revolver with pearl grips purchased by Major Taylor E. Brown prior to the Spanish-American War.