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imented on the value of an inch in the length of the barrel, an ounce in its weight, or a grain in the weight of the ball. They tried all methods of creasing, all variations of the spiral of the groove; every town had its gunsmith, who experimented in almost every gun he made, and who was generally one of the best shots and hunters in the neighborhood; and often the hunter, despairing of getting a gun to suit him in any other way, went to work himself, and wrought out a clumsy, but unerring gun, in which, perhaps, was the germ of some of the latest improvements in scientific gunnery. The different gun-makers had shooting-matches, at which the excellence of the work of each was put to the severest tests, and by which their reputations were established. The result is a rifle, compared with which, as manufactured by a dozen rifle-makers in the United States, the Minié, the Enfield, the Lancaster, or even the Sharpe's, and more recent breech-loaders, are bungling muskets. The last adopted form of missile, the sugar-loaf-shaped, of which the Minié, Enfield, Colonel Jacob's, and all the conical forms are partial adaptations, has been, to our personal knowledge, in use among our riflemen more than twenty years. In one of our earliest visits to that most fascinating of ateliers to most American youth, a gunsmith's shop, a collection of "slugs" was shown to us, in which the varieties of forms, ovate, conical, elliptical, and all nameless forms in which the length is greater than the diameter, had been exhausted in the effort to find that shape which would range farthest; and the shape (very nearly) which Colonel (late General) Jacob alludes to, writing in 1854, in these terms, "This shape, after hundreds of thousands of experiments, proves to be quite perfect," had been adopted by this unorganized ordnanceboard, composed of hundreds of gunmakers, stimulated by the most powerful incentives to exertion. The experiments by which they arrived at their conclusion not only anticipated by years the
trials of the European experimenters, but far surpass, in laboriousness and nicety, all the experiments of Hythe, Vincennes, and Jacobabad. The resulting curve, which the longitudinal section of the perfect "slug" shows, is as subtile and incapable of modification, without loss, as that of the boomerang; no hair's thickness could be taken away or added without injury to its range. Such a weapon and such a missile, in their perfection, could never have come into existence except in answer to the demand of a nation of hunters to whom a shade of greater accuracy is the means of subsistence. No man who is not a first-rate shot can judge justly of the value of a rifle; and one of our backwoodsmen would never use any rifle but the Kentucky of American manufacture, if it were given him. An Adirondack hunter would not thank the best English rifle-maker for one of his guns any more warmly than a sea-captain in want of a chronometer would thank his owners for a Swiss lepine watch.
The gun which we thus eulogize we shall describe, and compare the results which its use shows with those shown by the other known varieties of rifle, and this without any consideration of the powers of American marksmen as compared with European. The world is full of fables of shooting-exploits as absurd as those told of Robin Hood. Cooper tells of Leatherstocking's driving the nail with unfailing aim at a hundred paces, a degree of skill no man out of romance has ever been reported to possess amongst riflemen. We have seen the best marksmen the continent holds attempt to drive the nail at fifty yards, and take fifty balls to drive one nail. A story is current of a French rifleman shooting an Arab chief a mile distant, which, if true, was only a chance shot; for no human vision will serve the truest rifle ever made and the steadiest nerves ever strung to perform such a feat with any certainty. Lieutenant Busk informs us that Captain Minié "will undertake to hit a man at a dis
tance of 1420 yards three times out of five shots," a feat Captain Minié or any other man will "undertake" many times before accomplishing, for the simple reason, that, supposing the rifle perfect, at that distance a man is too small a mark to be found in the sights of a rifle, except by the aid of the telescope.* We could fill a page with marvellous shots quos vidi et quorum pars, etc. have seen a bird no larger than a halfgrown chicken killed off-hand at eighty rods (nearly fourteen hundred feet); have known a deer to be killed at a good half mile; have shot off the skullcap of a duck at thirty rods; at twenty rods have shot a loon through the head, putting the ball in at one eye and out at the other, without breaking the skin; but such shooting, ordinarily, is a physical impossibility, as any experienced rifleman. knows. These were chance shots, or so nearly so that they could not be repeated in a hundred shots. The impossibility lies in the marksman and in human vis
In comparing the effects of rifles, then, we shall suppose them, as in government trials and long-range shooting-matches, to be fired from a "dead rest," the only way in which the absolute power of a rifle can be shown. First, for the gun itself. There are two laws of gunnery which must be kept in sight in comparing the results of such trials:-1st, that the shape and material of two missiles being the same, the heavier will range the farther, because in proportion to its momentum it meets less resistance from the atmosphere; 2d, that the less the recoil of the gun, the greater will be the initial velocity of the ball, since the motion lost in recoil is taken from the velocity of the
A man, five feet ten inches high, at 1450 yards, will, in the back-sight of the Minié rifle, at fourteen inches from the eye, appear of an inch in height and in breadth
of shoulders. If the reader will look at these measures on a finely divided scale, he will appreciate the absurdity of such a boast. A man at that distance could hardly be found in the sights.
ball. Of course, then, the larger the bore of the rifle, the greater will be its range, supposing always the best form of missile and a proportionate weight of gun. As the result of these two laws, we see that of two guns throwing the same weight and description of missile, the heavier will throw its missile the farther; while of two guns of the same weight, that one which throws the smaller missile will give it the greater initial velocity,-supposing the gun free to recoil, as it must, fired from the shoulder. But the smaller ball will yield the sooner to the resistance of the atmosphere, owing to its greater proportional surface presented. Suppose, then, two balls of different weights to be fired from guns of the same weight;-the smaller ball will start with the higher rate of speed, but will finally be overtaken and passed by the larger ball; and the great problem of rifle-gauge is to ascertain that relation of weight of gun to weight of projectile which will give the greatest velocity at the longest range at which the object fired at can be seen distinctly enough to give a reasonable chance of hitting it. This problem the maker of the Kentucky rifle solves, by accepting, as a starting-point, the greatest weight of gun which a man may reasonably be expected to carry,-say, ten to twelve pounds, and giving to that weight the heaviest ball it will throw, without serious recoil, for no matter what the proportion, there will be some recoil. This proportion of the weight of gun to that of projectile, as found by experience, is about five hundred to one; so that if a gun weigh ten pounds, the ball should weigh about 5 of a pound. Of course, none of these gun-makers have ever made a mathematical formula expressing this relation; but hundreds of thousands of shots have pretty well determined it to be the most effective for all hunting needs (and the best hunting-rifles are the best for a rifle-corps, acting as sharp-shooters). By putting this weight of ball into a conical form of good proportions, the calibre of the gun may be made about ninety gauge, which, for a range of four hundred yards,
cannot be excelled in accuracy with that weight of gun.
But in a rifle the grooving is of the utmost importance; for velocity without accuracy is useless. To determine the best kind of groove has been, accordingly, the object of the most laborious investigations. The ball requires an initial rotary motion sufficient to keep it "spinning" up to its required range, and is found to gain in accuracy by increasing this rotatory speed; but if the pitch of the grooves be too great, the ball will refuse to follow them; but, being driven across them, "strips,”—that is, the lead in the grooves is torn off, and the ball goes out without rotation. The English gunsmiths have avoided the dilemma by giving the requisite pitch and making the grooves very deep, and even by having wings cast on the ball to keep it in the grooves,―expedients which increase the friction in the barrel and the resistance of the air enormously.
The American gun-makers have solved the problem by adopting the "gaining twist," in which the grooves start from the breech nearly parallel to the axis of the barrel, and gradually increase the spiral, until, at the muzzle, it has the pitch of one revolution in three to four; the pitch being greater as the bore is less. This gives, as a result, safety from stripping, and a rapid revolution at the exit, with comparatively little friction and shallow groove-marks on the ball, -accomplishing what is demanded of a rifled barrel, to a degree that no other combination of groove and form of missile ever has.
English makers have experimented somewhat on the rifling of barrels, but with no results which compare with those shown by the improved Kentucky. English hunting-rifles, and all military rifles, are made with complete disregard of the law of relation between the weights of ball and barrel. The former seems to be determined by dividing the weight of ammunition a soldier may carry in his cartridge-box by the number of charges he is required to have, and
then the gun is made as light as will stand the test of firing,- blunders all the way through; for we never want a rifleball to range much farther than it is possible to hit a single man with it; and a missile of the proper shape from a barrel of sixty gauge will kill a man at a mile's distance, if it strike a vital part. The consequence is, that the rifles are so light in proportion to their load that the recoil seriously diminishes the force of the ball, and entirely prevents accuracy of aim; and at the same time their elastic metal springs so much under the pressure of the gas generated by the explosion of the powder that anything like exactitude becomes impossible.* This the English gunsmiths do not seem to have learned, since their best authorities recommend a gun of sixty-four gauge to have a barrel of four pounds weight, and that is considered heavy, while ours, of sixty gauge, would weigh at least twice that. To get the best possible shooting, we find not only weight of barrel requisite, but a thickness of the metal nearly or quite equal to the diameter of the bore.
Mr. Whitworth, of Manchester, revived the old polygonal bore, and, by a far more perfect boring of barrel than was ever before attained in England, has succeeded in doing some very accurate shooting; but the pitch of his grooves requisite to give sufficient rotation to his polygonal missile to enable it to rotate to the end of its flight is so great, that the friction and recoil are enormous, and the liability to burst very great. Mr. Whitworth's missile is a twisted prism, corresponding to the bore, of two and a half diameters, with a cone at the front of one half the diameter. Such a gun, in a firing-machine, with powder enough to overcome all the friction, and heavy enough to counteract torsion and springing, would give very great accuracy, if perfectly
* Experiments have shown, that, with a barrel about the thickness of that of our "regulation rifles," the spring will throw a ball nearly two feet from the aim in a range of six hundred yards, if the barrel be firmly held in a machine.
made, or as well made as American rifles generally; but no maker in England, not even Mr. Whitworth, has attained that point yet; and even so made, they would never be available as service- or hunting-guns.
The Lancaster rifle avoids grooves (nominally) altogether, and substitutes an elliptical bore, twisted to Mr. Whitworth's pitch (twenty inches). General Jacob says, very justly, of this gun: "The mode of rifling is the very worst possible. It is only the two-grooved rifle in disguise. Let the shoulders of the grooves of a twogrooved rifle be removed, and you have the Lancaster rifle. But by the removal of these shoulders, the friction, if the twist be considerable, becomes enormous." To compare this twist with the rifled bore, one has only to take a lead tube, made slightly elliptical in its cross-section, and, fitting a plug to its ellipse, turn the plug round, and he will see that the result is to enlarge the whole bore to the longest diameter of the ellipse, which, if it were a gun-barrel, unelastic, would be equivalent to bursting it. But this is exactly the action which the ball has on the barrel, so that, to use General Jacob's words, "the heat developed by the friction must be very great, and the tendency of the gun to burst also very great.” Lieutenant Busk-who seems, if we may judge from the internal evidence of his book, to know little or nothing of good rifles or rifle-practice, and to have no greater qualification for writing the book than the reading of what has been written on the subject and an acquaintance of great extent with gunsmiths-remarks, in reply to the veteran of English riflemen: "Having given the matter the very closest attention, I am enabled confidently to state that the whole of this supposition [quoted above] is founded in error...... So far from the friction being enormous, it is less than that generated in any other kind of rifle. It is also utterly impossible for the bullet to act destructively on the barrel in the way suggested." Such cool assurance, in an unsupported contradiction of ex
perience and the dictates of the simplest mechanical common-sense, would seem to promise little real value in the book, and promises no less than it really has.
The same objection which lies against the Lancaster rifle (?) applies to the Whitworth in a less degree. If the reader, having tried the lead-pipe experiment above, will next hammer the tube hexagonal and try the plug again, he will find the same result; but if he will try it with a round bore grooved, and with a plug fitting the grooves, he will see that the pressure is against the wall of the groove, and acts at right angles to the radius of the bore, having only a tendency to twist the barrel in order to straighten the grooves, a tendency which the barrel meets in the direction of its greatest stability. We may see, then, that, in theory at least, there is no way of rifling so secure as that in which the walls of the grooves are parts of radii of the bore. They should be numerous, that the hold of the lands (the projection left between the grooves) may divide the friction and resistance as much as possible, and so permit the grooves to be as shallow as may be. The figure
represents, on one side of the dotted line, three grooves, 1, 1, 1, cut in this way, exaggerated to show more clearly their character. In the Kentucky rifle this law is followed, except that, for convenience in cutting, the grooves are made of the same width at the bottom and top, as shown at 2, 2, 2, which is, for grooves of the depth of which they are made, practically the same, as the dotted circle will show. Our gun-makers use from six to ten grooves.
To sum up our conditions,-the model rifle will conform to the following description:-Its weight will be from ten to twelve pounds; the length of barrel not
less than thirty inches,* and of calibre from ninety to sixty gauge; six to ten freed grooves, about .005 inch deep, angular at bottom and top, with the lands of the same width as the grooves; twist increasing from six feet to three feet; barrel, of cast steel, fitted to the stock with a patent breech, with back action set lock, and open or hunting and globe and peek sights. Mr. Chapman, whose book is the most interesting and intelligent, by far, of all hitherto published, recommends a straighter stock than those generally used by American hunters. Here we differ;-the Swiss stock, crooking, on an average, two inches more than ours, is preferable for quick shooting, though in a light rifle much crook in the stock will throw the muzzle up by the recoil. With such a gun,—the best for hunting that the ingenuity and skill of man have ever yet contrived and made,-one may depend on his shot, if he have skill, as he cannot on the Minié, Enfield, or Lancaster; and whether he be in the field against a foe, or in the forest against the deer, he holds the life of man or deer in his power at the range of rifle-sighting.
* There is much difference of opinion amongst gun-makers as to the length of barrel most desirable. We believe in a long barrel, for the following reasons: 1st, a longer distance between sights is given, and the back sight can be put farther from the eye, so that finer sighting is possible; 2d, a long barrel is steadier in off-hand shooting; 3d, it permits a slower powder to be used, so that the ball starts more slowly and yet allows the full strength of the powder to be used before it leaves the barrel, getting a high initial velocity with little recoil, and without "upsetting" the ball, as we shall explain farther on. The experiments of the United States government show that the increasing of the length of the barrel from thirty-three to forty inches (we. speak from memory as to numbers) increased the initial velocity fifty feet per second; but this will, in long ranges, be no advantage, except with such a shape of missile as will maintain a high speed.
† Hunters still dispute as to iron or steel; and we have used iron barrels made by Amsden, of Saratoga Springs, which for accuracy and wear were unexceptionable; though gunsmiths generally take less pains with iron than steel barrels. But give us steel.
Of all the variations of the rifle, for the sake of obtaining force of penetration, nothing yet compares with the Accelerating Rifle, invented some years since by a New York mechanic. In this the ball was started by an ordinary charge, and at a certain distance down the barrel received a new charge, by a side chamber, which produced an almost incredible effect. An ellipsoidal missile of ninety gauge and several diameters long, made of brass, was driven through thirty-six inches of oak and twenty-four inches of green spruce timber, or fifty inches of the most impenetrable of timbers. The same principle of acceleration has, it is said, been most successfully applied in Boston by the use of a hollow tige or tube fixed at the bottom of the bore with the inside of which the cap-fire communicates,—so that, when the gun is charged, part of the powder falls into the tige, and the remainder into the barrel outside of it. The ball being driven down until it rests on the top of the tige, receives its first impulse from the small charge contained in it, after which, the fire, flashing back, communicates to the powder outside the tige, producing an enormous accelerating effect. But it is doubtful if the gun can be brought into actual service, from being so difficult to clean.
It is questionable if any greater range in rifles will be found desirable. With a good Kentucky rifle, we are even now obliged to use telescope sights to avail ourselves of its full range and accuracy of fire. The accelerating inventions may be made use of in artillery, for throwing shells, and for siege trains, but promise nothing for small arms.
Then, as the secondary point, comes the form of projectile, that in which the greatest weight (and thence momentum) combines with least resistance from the atmosphere. In the pursuit of this result every experimenter since the fifteenth century has worked. Lautmann, writing in 1729, recommends an elliptical missile, hollow behind, from a notion that the hollow gathered the explosive force. Robins recommends elongated balls; and they