Patent: Thompson

Britain 772

A.D. 1879, 26th February. № 772.

Smooth-bore Revolvers.

(This Invention received Provisional Protection only.)

PROVISIONAL SPECIFICATION left by William Phillips Thompson at the Office of the Commissioners of Patents on the 26th February 1879. A communication from abroad from William Castles Dodge, of Washington, in the District of Columbia, United States.

William Phillips Thompson, of the Firm of W. P. Thompson and Co., Patent. Agenis and Consulting Engineers, of 6, Lord Street, Liverpool, in the County of Lancaster, and 323, High Holborn, in the County of Middlesex. “Improvements in and Relating to Smooth-bore Cartridge Shot Revolvers.” A communication from abroad from William Castles Dodge, of Washington, in the District of Columbia, United States.

My Invention relates to that class of fire arms designated as revolvers, and the Invention consists of a revolving cylinder having its chambers extending entirely through it from end to end, in combination with a smooth bore single barrel in front whereby an arm is produced specially adapted to shooting shot instead of the bullets ordinarily used in this class of arms as hereinafter more fully set forth.

The object of this Invention is to produce an arm specially adapted for the defence of houses, et cetera, against burglars, robbers, and the like, and where it is often’ necessary to use an arm in the dark when it is impossible to take accurate aim, and also for military use.

In constructing an arm on my plan I make the frame in the usual manner or of any desired pattern or style, I then provide a cylinder which has its chambers bored entirely through from end to end, so that it may be loaded from the rear by the insertion of flanged metallic cartridges, as is also usual with ordinary revolvers at the present day, This cylinder is mounted in the frame, which latter is provided with a lock and mechanism for rotating the cylinder and a stop for holding it in position when fired, the same as in ordinary revolvers, though I prefer to use what is known as a self cocking lock, that is, one in which the hammer may be both cocked and released by simply pulling the trigger, of which there are various kinds known to the trade, and which therefore need not be specially described. I then provide a single barrel which is secured to the frame in front of the cylinder in the usual manner; but this barrel instead of being rifled or grooved, as has heretofore been the practice, I make with a smooth bore. The object of using this style of barrel is to enable the shot to pass readily through it without jamming or wedging in the grooves or against the edge of the lands as they would if the barrel was rifled. In order to enable the arm to be used with convenience and be loaded with ease and rapidity I propose to use metallic cartridge shells and charge the same with powder and buck-shot, the powder being first put in, then wad, then the buck-shot, and finally another wad to hold the-.shot in.

To produce the best results the chambers of the cylinder should be of such a size as to receive a cartridge that will chamber the shot in such manner that a layer of shot will fit the barrel with their centres all in the same transverse plane’ without unnecessary waste room, so that they will not jam or wedge in the chamber or in the barrel and will thus pass through the barrel with less friction and without being crushed out of form or shape. By this means the shot will be thrown with more force and accuracy.

In a short arm like a revolver it is necessary that the force of the powder shall be exerted upon the shot throughout the entire length of the barrel, in order to project the shot with the required force; and to do this the chambers of the cylinder should be bored enough larger than the bore of the barrel to enable a cartridge shell to be used of such a size that its interior diameter shall be equal to the diameter of the bore of the barrel, so that the shot and wad shall have a continuous passage of uniform diameter and thus prevent the escape of gas past the edge of the wad which is behind the shot, as any gas escaping past the wad would of course be lost and would not aid to propel the shot. In case thin shells are used and the wads contracted somewhat, as they naturally would be in forcing them into the shells, then it may suffice to have the chambers of the cylinder and the bore of the barrel of uniform diameter, because in that case the wads as they are forced from the shell will expand and fill the bore of the barrel and thus operate to prevent the escape of the gas past them; but I prefer that the chambers shall be slightly larger in diameter than the bore of the barrel, for the reason stated. It will of course be understood that the muzzle of the barrel may be slightly expanded or contracted in order to regulate the scattering of the shot, the same as in ordinary shot guns. The advantages of such an arm for the purposes named are apparent. It frequently happens that when one is attacked by burglars or robbers several shots are fired from the ordinary revolver without effect, owing to the darkness or to the un-steadiness of the aim on account of the excitement or fright. With an arm like this carrying six or nine buck-shot it will be almost impossible for the assailant to escape without injury, for even if it be in the dark, or there be no chance to take aim, the numerous and scattering shot will some of them be pretty sure to hit the object if the arm be merely pointed in the right direction and fired.

While I have described it as adapted to use buck-shot it is obvious that it may be made to use shot of other sizes equally well and thus the arm may be reduced in size. By using the coarser sizes of bird shot a larger number of shot may be used and a larger space thus covered by them.

Another advantage of such an arm is that while it is less likely to produce death, it is far more likely to produce wounds and thus lead to the detection and consequent legal punishment of the guilty parties, As a means of defence against vicious animals, and for express messengers and watchmen, it will be far more efficient than the ordinary revolver.

It is also obvious that shot guns may be constructed on the same plan for sporting purposes or for defencive use.