Tower of London, but this was subsequently improved by
introducing geared mechanism, by which the pull of the trigger
or the cocking of the hammer, or both, do the work. There
exists a pistol of the time of Charles I. which is rotated automatically
as the hammer is raised.
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| Fig. 2—Wheel-lock pistol (Royal United Service Institution). |
In 1814 a self-acting revolver mechanism of a crude pattern was produced in England. Four years later Collier used a separate spring to rotate the chamber. In 1835, an American, Samuel Colt, produced and patented the first practical revolving pistol, the idea of which was obtained by him, it is stated, from an ancient “revolving” weapon in the Tower of London. The chambers of the first Colt revolver were loaded with powder and bullets from the muzzle end, and each chamber had a nipple that required to be capped. It was the invention of the copper cap that made the Colt revolver possible. Under the old priming system with exposed powder in a pan the difficulty of separate and effective ignition with the revolving cylinder was almost insuperable.
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| Fig. 3.—Wheel-lock pistol (Royal United Service Institution). |
The first American revolver makers caused the cocking of the hammer to revolve the cylinder, while the English makers effected this by the pull of the trigger. In 1855, Adams of London, and also Tranter of Birmingham, brought out the double-action revolver, in which the revolution of the cylinder could be effected by both these methods. When the revolver is cocked and fired by pressing the trigger, greater rapidity of fire is obtained than when the hammer is cocked with the thumb, but accuracy is impaired, as the trigger requires a long pull and considerable force in order to compress the mainspring and revolve the cylinder. The double action revolver was, therefore, a great advance on the single action, enabling the first and also following shots, if desired, to be accurately fired by a moderate pressure of the trigger after the hammer had been cocked by the thumb; or, alternatively, the revolver could be rapidly fired, if necessary, by the trigger action alone. Many revolvers on the Colt principle were in use during the Crimean War and the Indian Mutiny, and proved of valuable service to British officers.
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| Fig. 4.—Flint-lock pistol (Royal United Service Institution). |
As rim-fire, pin-fire and central-fire cartridges were successively introduced, breech-loading revolvers were constructed to use them. Messrs Smith & Wesson, of Springfield, U.S.A., produced the first metal cartridges for revolvers. Pin-fire cartridges, paper and metallic, were used on the continent of Europe for Lefaucheux and other revolvers, and these and rim-fire cartridges are still used for revolvers of small calibre. But since the central-fire cartridge has proved its superiority for guns, its principle has been generally applied to pistol cartridges, at first to the larger bores.
The alteration of the muzzle-loading to the breech-loading chamber in the revolver involved no decided change of type. The original Colt, as a breech-loader, remained practically the same weapon as before, with a changed chamber. A hinged flap uncovered the breech-chamber on the right, and as each chamber reached that point the empty cartridge case was ejected by means of an ejecting-rod carried in a tube attached to the under side of the barrel and kept in place by a spiral spring, and the chamber reloaded. The next improvement was greater ease and rapidity of extraction, obtained first by Thomas’s invention of making the barrel and chamber slide forward on the frame of the pistol. The extractor, being fast to the pivot, retained the cartridges until the chamber was pushed clear of them. Then the chamber was made to swing on one side, as in the Colt pistol illustrated, enabling all the cartridges to be simultaneously extracted. Finally, self-extracting revolvers with jointed frames were introduced, in which the dropping of the barrel forces out the extractor as in an ordinary double gun, the extractor acting simultaneously in all the chambers of
