THE COLT DOUBLE ACTION REVOLVER
AN INTRODUCTION
The history of the Colt double action revolver starts with Samuel Colt himself.
Colt preferred his single action designs and made it clear that he hated the double action system. He thought it disturbed the aim and prevented good accuracy. As long as Colt lived, Colt Firearms would never sell a double action revolver.
As soon as Colt began marketing his revolver others began violating Colt's patents by making copies or versions of his idea.
Colt would spend a good part of the rest of his life hunting down and suing violators of his patents.
As soon as his patents expired in Europe, there was a mass rush to design and sell revolving pistols.
Among the most prolific were the British and Belgians, who immediately began designing revolvers often with a double action trigger.
It was 15 years after Samuel Colt's death that Colt Firearms finally marketed a double action revolver.

The first Colt to have a double action trigger was the Model 1877.
The 1877 was the first of a number of versions of a double action pistol design that resembled the Colt Single Action Army of 1873 and used some SAA parts, modifed for a DA trigger.
The new double action design utilized the same type loading system of the SAA, a pivoting loading gate and an ejector mounted along the barrel, and a rounded, "Bird's head" grip.
Colt offered a number of options including short barrels without ejector rods, and with barrels as long as 12 inches.
Following Colt's standard practice, the 1877 design was continually manufactured as long as it was selling, even though newer, superior designs were already being marketed by Colt.
The 1877 was made in various forms as late as the Model 1904 Philippine Constabulary.

The next double action revolver Colt fielded was revolutionary.
In 1889 Colt introduced the world's first double action, swing-out cylinder revolver. This design was so effective and strong, it became the standard for all double action designs that followed.
The 1889 was named the New Navy Model of 1889. When the design was also bought by the Army in 1892 the name was changed to the Colt New Army & Navy Model.
Following standard Colt practice, the 1889 was quickly followed up by improved versions each with it's own model number as the Models 1894, 1895, 1896, 1901, and 1903.
These new swing-out cylinder revolvers were made as both military issue and commercial sales firearms, and were extremely popular, selling several hundred thousand guns.

In 1895 Colt brought out a totally new design action in the Colt New pocket revolver.
This was a small frame concealable double action that was the ancestor of all Colt's to follow until 1969. Only slightly modified over the years, this action was the basis for virtually every Colt double action revolver to follow. It was last used in the Colt Python until it was discontinued in 2003-2004.

The next advance in double action design came in 1898 with the Colt New Service.
The New Service was a large frame revolver intended for the most powerful cartridges of the day.

Meanwhile, Colt was modifying the Pocket Model into what would be Colt's small frame revolver, the Police Positive, made for short cartridges, and the Police Positive Special made for the longer .38 Special.
It was the Police Positive Special that would be made as one of Colt’s most popular and famous guns, the Colt Detective Special.

In 1908 Colt introduced the revolver that would set the standard for the next 60 years.
This new medium frame revolver was known as the Colt Army Special. It was the replacement for the overly complex, fragile New Army & Navy models.
The Army Special was an immediate hit with law enforcement and civilians and sold very well. The Army Special was the basis for every Colt medium frame revolver that would follow and was made in a number of formats from service pistols to target revolvers.

After World War Two, Colt began developing firearms made from new materials.
In 1950, Colt introduced a small frame revolver based on the Detective Special using an aluminum frame. The Cobra and Agent were the worlds first aluminum framed revolvers and would be best sellers for many years.

In the late 1960's the cost of Colt revolvers was pricing them out of the highly competitive market because of the extensive hand labor needed to build them.
Colt decided to develop an entirely new action design, the first since the Army Special of 1908. This new design would take full advantage of the latest manufacturing methods, and would eliminate as much hand labor as possible.
In 1969 Colt introduced this new design as the Mark III.
This was a totally new revolver with nothing in common with the older guns.
Instead of the old Colt Positive Safety design which employed a rebounding hammer and internal hammer block system, the new design used a transfer bar safety and ignition system.
In this system, when the trigger is pulled, a steel block rises up between the hammer and the frame mounted firing pin. When the hammer drops it strikes the transfer bar which in turn strikes the firing pin, transferring the force.
If the trigger is released, the transfer bar instantly drops down and the hammer cannot contact the firing pin.
This new system was very safe and was both less complex and cheaper to manufacture.

The new revolver was manufactured using internal parts made of "sintered" steel. This is a process in which powdered steel is heated in a mold until it melts, filling the mold.
When the mold is opened, a virtually finished part is ready for surface hardening and finishing.

Since these molded parts could be made to very tight tolerances, this allowed less skilled production personnel to assemble the guns.
When building a new Mark III revolver, the production fitter would pull a part from a bin full of parts and test fit it. If the part wasn't a perfect fit, the assembler simply selected another part from the bin until one did fit correctly. This was much faster than the old way of a Master assembler hand filing, stoning, and bending parts to build a gun.
This new design revolver was extremely strong, and was said by Master gunsmith Jerry Kuhnhausen to be possibly the strongest medium frame, double action revolver ever made.
As with the Army Special, Colt used the basic Mark III action as the basis for an entire series of revolvers ranging from a fixed sight .38 Special service revolver to the deluxe Trooper Mark III .357 Magnum adjustable sight model.
In 1983 Colt introduced a slightly modified version of the Mark III as the Mark V.

In the early 1980's Colt introduced stainless steel to their line of revolvers with the first stainless steel Pythons.
In 1985, Colt used a slightly modified version of the Mark V to make a stainless steel revolver as the King Cobra.

In the 1990's, Colt introduced two new double action revolvers. The first was the new Anaconda .44 Magnum, the first large frame Colt made since the New Service was discontinued during World War Two. The second was a new small frame revolver, the .38 Special Colt SF-VI. The SF-VI was also made as the DS-II and the Magnum Carry in .357 Magnum, Colt's first small frame Magnum revolver.
These later Colt's were made of stainless steel, and were based on the King Cobra design.

In the 1970's Colt began to experience turbulence as a company. Being a small part of a huge corporation which Colt Firearms had founded, the corporation seemed unsure just what to do with the comparatively small Firearms Division.
Every year of so a new Firearms Division president was sent down by the corporate headquarters. Most of these men knew nothing about firearms or firearms manufacturing, and it was apparent that some were interested only in making a good impression so they could get promoted within the corporation and away from the firearms part of it.
Attempting to make his mark, each ordered old models discontinued, new models to be introduced and the old discontinued models to be re-introduced.
This, among many other causes eventually led Colt Firearms Division to go bankrupt and be sold by the corporation to new owners.
The new owners were forced to discontinue a number of Colt firearms in 2000, including all the double actions except the Python and the Anaconda.
With revolver sales down in an era of large capacity automatic pistols, and the Python too expensive and difficult to produce, Colt finally discontinued the last of the famous Colt double actions. The last to go were the Anaconda and the famed Python in 2003-2004.

COLT DOUBLE ACTION REVOLVER AMMUNITION
In the 1800's and early 1900's Colt developed a number of cartridges for their pistols.  They also chambered Colt pistols in popular cartridges developed by other companies.  Not wanting a competitors name on a Colt firearm, Colt often simply re-named the cartridge with a Colt brand name or developed a cartridge so much like it, it was interchangeable.
As example, Colt didn't want rival Smith & Wesson's name on a Colt revolver, so they simply called the .32 S&W the .32 New Police and the .38 S&W the .38 New Police.
Since most Colt's had long chambers they could chamber both short and long versions of a cartridge.  Therefore, most .38 Colt's could chamber both the .38 Colt Long and Short, and the .41 Colt could chamber both the .41 Colt Long and Short.
With the introduction of the .38 Special, most of these older low pressure black powder era cartridges began to fade, and by World War Two most had disappeared as Colt chamberings.  Bowing to the inevitable, Colt discontinued the New Police markings and used the S&W names for these short cartridges until they finally disappeared as Colt chamberings in the 1960's.
Colt began offering modern cartridges in the 1930's with chambering the New Service and Single Action Army in the then new .357 Magnum developed by Daniel Wesson of Smith & Wesson.
After World War Two, Colt began making more use of the .357, being the first gun company to offer it in a medium frame revolver, the Colt 357 model.
It was only in the 1990's that Colt finally developed a large frame revolver to replace the pre-War New Service.  The new Colt Anaconda was the first double action revolver Colt made in .44 Magnum.