Imatges de pÓgina
PDF
EPUB

imented on the value of an inch in the trials of the European experimenters, length of the barrel, an ounce in its but far surpass, in laboriousness and weight, or a grain in the weight of the nicety, all the experiments of Hythe, ball. They tried all methods of creas- Vincennes, and Jacobabad.

The reing, all variations of the spiral of the sulting curve, which the longitudinal secgroove; every town had its gunsmith, tion of the perfect "slug" shows, is as who experimented in almost every gun subtile and incapable of modification, he made, and who was generally one without loss, as that of the boomerang; of the best shots and hunters in the no hair's thickness could be taken away neighborhood; and often the hunter, de- or added without injury to its range. spairing of getting a gun to suit him in Such a weapon and such a missile, in any other way, went to work himself, their perfection, could never have come and wrought out a clumsy, but unerring into existence except in answer to the gun, in which, perhaps, was the germ of demand of a nation of hunters to whom some of the latest improvements in scien- a shade of greater accuracy is the means tific gunnery. The different gun-makers of subsistence. No man who is not a had shooting-matches, at which the ex- first-rate shot can judge justly of the cellence of the work of each was put to value of a rifle; and one of our backthe severest tests, and by which their woodsmen would never use any rifle but reputations were established.

The re

the Kentucky of American manufacture, sult is a rifle, compared with which, as if it were given him. An Adirondack manufactured by a dozen rifle-makers in hunter would not thank the best Eng. the United States, the Minié, the En- lish rifle-maker for one of his guns any field, the Lancaster, or even the Sharpe's, more warmly than a sea-captain in want and more recent breech-loaders, are bun- of a chronometer would thank his owngling muskets. The last adopted form ers for a Swiss lepine watch. of missile, the sugar-loaf-shaped, of which The gun which we thus eulogize we the Minié, Enfield, Colonel Jacob's, and shall describe, and compare the results all the conical forms are partial adap- which its use shows with those shown by tations, has been, to our personal knowl- the other known varieties of rifle, and edge, in use among our riflemen more this without any consideration of the than twenty years. In one of our ear- powers of American marksmen as comliest visits to that most fascinating of pared with European. The world is full ateliers to most American youth, a gun- of fables of shooting-exploits as absurd smith's shop, a collection of " slugs” was as those told of Robin Hood. Cooper shown to us, in which the varieties of tells of Leatherstocking's driving the forms, ovate, conical, elliptical, and all nail with unfailing aim at a hundred nameless forms in which the length is paces,- a degree of skill no man out of greater than the diameter, had been ex- romance has ever been reported to poshausted in the effort to find that shape sess amongst riflemen. We have seen which would range farthest; and the the best marksmen the continent holds shape (very nearly) which Colonel (late attempt to drive the nail at fifty yards, General) Jacob alludes to, writing in and take fifty balls to drive one nail. A 1854, in these terms, “ This shape, after story is current of a French rifleman hundreds of thousands of experiments, shooting an Arab chief a mile distant, proves to be quite perfect,” had been which, if true, was only a chance shot; adopted by this unorganized ordnance- for no human vision will serve the truboard, composed of hundreds of gun- est rifle ever made and the steadiest makers, stimulated by the most powerful nerves ever strung to perform such a incentives to exertion. The experiinents feat with any certainty. Lieutenant by which they arrived at their conclu- Busk informs us that Captain Minié sion not only anticipated by years the " will undertake to hit a man at a distance of 1420 yards three times out of ball. Of course, then, the larger the bore five shots,” — a feat Captain Minié or of the rifle, the greater will be its range, any other man will “ undertake ” many supposing always the best form of missile times before accomplishing, for the sim- and a proportionate weight of gun. As ple reason, that, supposing the rifle per the result of these two laws, we see that fect, at that distance a man is too small of two guns throwing the same weight a mark to be found in the sights of a and description of missile, the heavier rifle, except by the aid of the telescope.* will throw its missile the farther; while We could fill a page with marvellous of two guns of the same weight, that one shots quos vidi et quorum pars, etc. We which throws the smaller missile will give have seen a bird no larger than a half- it the greater initial velocity, — supposing grown chicken killed off-band at eighty the gun free to recoil, as it must, fired rods (nearly fourteen hundred feet); from the shoulder. But the smaller ball have known a deer to be killed at a will yield the sooner to the resistance of good half mile; have shot off the skull- the atmosphere, owing to its greater procap of a duck at thirty rods; at twenty portional surface presented. Suppose, rods have shot a loon through the head, then, two balls of different weights to be putting the ball in at one eye and out at fired from guns of the same weight; - the the other, without breaking the skin ;- smaller ball will start with the higher rate but such shooting, ordinarily, is a physical of speed, but will finally be overtaken impossibility, as any experienced rifleman and passed by the larger ball; and the knows. These were chance shots, or so great problem of rifle-gauge is to ascertain nearly so that they could not be repeated that relation of weight of gun to weight in a hundred shots. The impossibility of projectile which will give the greatest lies in the marksman and in human vis- velocity at the longest range at which the ion.

object fired at can be seen distinctly In comparing the effects of rifles, then, enough to give a reasonable chance of we shall suppose them, as in government hitting it. This problem the maker of trials and long-range shooting-matches, the Kentucky rifle solves, by accepting, to be fired from a “dead rest,”— the only as a starting-point, the greatest weight way in which the absolute power of a of gun which a man may reasonably be rifle can be shown. First, for the gun expected to carry, -say, ten to twelve itself. There are two laws of gunnery pounds,- and giving to that weight the which must be kept in sight in compar- heaviest ball it will throw, without serious ing the results of such trials :— 1st, that recoil, – for no matter what the proporthe shape and material of two missiles be- tion, there will be some recoil. This pra ing the same, the heavier will range the portion of the weight of gun to that of profarther, because in proportion to its mo- jectile, as found by experience, is about mentum it meets less resistance from the five hundred to one; so that if a gun atmosphere; 2d, that the less the recoil weigh ten pounds, the ball should weigh of the gun, the greater will be the initial about sooo of a pound. Of course, none velocity of the ball, since the motion lost of these gun-makers have ever made a in recoil is taken from the velocity of the mathematical formula expressing this re

lation ; but hundreds of thousands of shots * A man, five feet ten inches high, at 1450 have pretty well determined it to be the yards, will, in the back-sight of the Minié most effective for all hunting needs (and rifle, at fourteen inches from the eye, appear the best hunting-rifles are the best for a o's of an inch in height and 5 in breadth

rifle-corps, acting as sharp-shooters). By of shoulders. If the reader will look at these

putting this weight of ball into a conical measures on a finely divided scale, he will appreciate the absurdity of such a boast. A

form of good proportions, the calibre of man at that distance could hardly be found

the gun may be made about ninety gauge, in the sights.

which, for a range of four hundred yards,

cannot be excelled in accuracy with that then the gun is made as light as will weight of gun.

stand the test of firing, blunders all the But in a rifle the grooving is of the way through; for we never want a rifleutmost importance; for velocity without ball to range much farther than it is posaccuracy is useless. To determine the sible to hit a single man with it; and a best kind of groove has been, according- missile of the proper shape from a barly, the object of the most laborious inves- rel of sixty gauge will kill a man at a tigations. The ball requires an initial ro- mile's distance, if it strike a vital part. tary motion sufficient to keep it “ spin- The consequence is, that the rifles are so ning” up to its required range, and is light in proportion to their load that the found to gain in accuracy by increasing recoil seriously diminishes the force of this rotatory speed; but if the pitch of the ball, and entirely prevents accuracy the grooves be too great, the ball will re- of aim; and at the same time their elastic fuse to follow them ; but, being driven metal springs so much under the pressure across them, “ strips,”—that is, the lead in of the gas generated by the explosion of the grooves is torn off, and the ball goes the powder that anything like exactitude out without rotation. The English gun- becomes impossible. This the English smiths have avoided the dilemma by giv- gunsmiths do not seem to have learned, ing the requisite pitch and making the since their best authorities recommend a grooves very deep, and even by having gun of sixty-four gauge to have a barrel wings cast on the ball to keep it in the of four pounds weight, and that is considgrooves,-expedients which increase the ered heavy, — while ours, of sixty gauge, friction in the barrel and the resistance would weigh at least twice that. To get of the air enormously.

the best possible shooting, we find not onThe American gun-makers have solved ly weight of barrel requisite, but a thickthe problem by adopting the “gaining ness of the metal nearly or quite equal to twist,” in which the grooves start from the diameter of the bore. the breech nearly parallel to the axis of Mr. Whitworth, of Manchester, rerivthe barrel, and gradually increase the ed the old polygonal bore, and, by a far spiral, until, at the muzzle, it has the more perfect boring of barrel than was pitch of one revolution in three to four; ever before attained in England, has sucthe pitch being greater as the bore is ceeded in doing some very accurate less. This gives, as a result, safety from shooting; but the pitch of his grooves stripping, and a rapid revolution at the requisite to give sufficient rotation to his exit, with comparatively little friction polygonal missile to enable it to rotate to and shallow groove-marks on the ball, the end of its flight is so great, that the -accomplishing what is demanded of a friction and recoil are enormous, and the rifled barrel, to a degree that no other liability to burst very great. Mr. Whitcombination of groove and form of mis- worth's missile is a twisted prism, corresile ever has.

sponding to the bore, of two and a half English makers have experimented diameters, with a cone at the front of one somewhat on the rifling of barrels, but half the diameter. Such a gun, in a firwith no results which compare with ing-machine, with powder enough to overthose shown by the improved Kentucky. come all the friction, and heavy enough English hunting-rifles, and all military to counteract torsion and springing, would rifles, are made with complete disregard give very great accuracy, if perfectly of the law of relation between the weights of ball and barrel. The former * Experiments have shown, that, with a seems to be determined by dividing the

barrel about the thickness of that of our “reg

ulation rifles," the spring will throw a ball weight of ammunition a soldier may car

nearly two feet from the aim in a range of ry in his cartridge-box by the number six hundred yards, if the barrel be firmly of charges he is required to have, and held in a machine.

made, or as well made as American rifles perience and the dictates of the simplest generally; but no maker in England, not mechanical common-sense, would seem even Mr. Whitworth, has attained that to promise little real value in the book, point yet; and even so made, they would and promises no less than it really never be available as service- or hunt- has. ing-guns.

The same objection which lies against The Lancaster rifle avoids grooves the Lancaster rifle (?) applies to the (nominally) altogether, and substitutes Whitworth in a less degree. If the readan elliptical bore, twisted to Mr. Whit- er, having tried the lead-pipe experiment worth’s pitch (twenty inches). General above, will next hammer the tube hexJacob says, very justly, of this gun : “ The agonal and try the plug again, he will mode of rifling is the very worst possible. find the same result; but if he will try it It is only the two-grooved rifle in disguise. with a round bore grooved, and with a Let the shoulders of the grooves of a two- plug fitting the grooves, he will see that grooved rifle be removed, and you have the pressure is against the wall of the the Lancaster rifle. But by the removal groove, and acts at right angles to the of these shoulders, the friction, if the radius of the bore, having only a tentwist be considerable, becomes enormous.” dency to twist the barrel in order to To compare this twist with the rifled straighten the grooves, - a tendency bore, one has only to take a lead tube, which the barrel meets in the direction made slightly elliptical in its cross-sec- of its greatest stability. We may see, tion, and, fitting a plug to its ellipse, turn then, that, in theory at least, there is no the plug round, and he will see that the way of rifling so secure as that in which result is to enlarge the whole bore to the the walls of the grooves are parts of radii longest diameter of the ellipse, which, if of the bore. They should be numerous, it were a gun-barrel, unelastic, would be that the hold of the lands (the projection equivalent to bursting it. But this is ex- left between the grooves) may divide actly the action which the ball has on the the friction and resistance as much as barrel, so that, to use General Jacob's possible, and so permit the grooves to words, “ the heat developed by the fric- be as shallow as may be. The figure tion must be very great, and the tenden

represents, cy of the gun to burst also very great."

one side of the Lieutenant Busk — who seems, if we

dotted line, three may judge from the internal evidence

grooves, 1, 1, 1, of his book, to know little or nothing of

cut in this way, good rifles or rifle-practice, and to have

exaggerated to no greater qualification for writing the

show more clearbook than the reading of what has been

ly their characwritten on the subject and an acquaint

ter. In the Kenance of great extent with gunsmiths-re- tucky rifle this law is followed, except marks, in reply to the veteran of English that, for convenience in cutting, the riflemen: “Having given the matter the grooves are made of the same width at very closest attention, I am enabled con- the bottom and top, as shown at 2, 2, 2, fidently to state that the whole of this which is, for grooves of the depth of supposition [quoted above) is founded in which they are made, practically the error. ..... So far from the friction be- same, as the dotted circle will show. ing enormous, it is less than that gener- Our gun-makers use from six to ten ated in any other kind of rifle. It is grooves. also utterly impossible for the bullet to To sum up our conditions, the modact destructively on the barrel in the el rifle will conform to the following deway suggested.” Such cool assurance, scription :- Its weight will be from ten to in an unsupported contradiction of ex- twelve pounds; the length of barrel not

on

1

less than thirty inches, * and of calibre Of all the variations of the rifle, for from ninety to sixty gauge; six to ten the sake of obtaining force of penetrafreed grooves, about .005 inch deep, an- tion, nothing yet compares with the Acgular at bottom and top, with the landscelerating Rifle, invented some years since of the same width as the grooves; twist by a New York mechanic. In this the increasing from six feet to three feet; ball was started by an ordinary charge, barrel, of cast steel,t fitted to the stock and at a certain distance down the barrel with a patent breech, with back action set received a new charge, by a side chamlock, and open or hunting and globe and ber, which produced an almost incredible peek sights. Mr. Chapman, whose book effect. An ellipsoidal missile of ninety is the most interesting and intelligent, by gauge and several diameters long, made far, of all hitherto published, recommends of brass, was driven through thirty-six a straighter stock than those generally inches of oak and twenty-four inches of used by American hunters. Here we green spruce timber, or fifty inches of the differ;—the Swiss stock, crooking, on an most impenetrable of timbers. The same average, two inches more than ours, is principle of acceleration has, it is said, preferable for quick shooting, though in a been most successfully applied in Boston light rifle much crook in the stock will by the use of a hollow tige or tube fixed throw the muzzle up by the recoil. With at the bottom of the bore with the inside such a gun,--the best for hunting that the of which the cap-fire communicates,--so ingenuity and skill of man have ever yet that, when the gun is charged, part of contrived and made,-one may depend the powder falls into the tige, and the on his shot, if he have skill, as he can- remainder into the barrel outside of it. not on the Minié, Enfield, or Lancaster; The ball being driven down until it rests and whether he be in the field against a on the top of the tige, receives its first imfoe, or in the forest against the deer, he pulse from the small charge contained in holds the life of man or deer in his power it,- after which, the fire, flashing back, at the range of rifle-sighting,

communicates to the powder outside the * There is much difference of opinion tige, producing an enormous accelerating amongst gun-makers as to the length of bar- effect. But it is doubtful if the gun can rel most desirable. We believe in a long bar

be brought into actual service, from being rel, for the following reasons: 1st, a longer

so difficult to clean. distance between sights is given, and the back sight can be put farther from the eye, so that

It is questionable if any greater range finer sighting is possible; 2d, a long barrel

in rifles will be found desirable. With a is steadier in off-hand shooting; 3d, it per- good Kentucky rifle, we are even now mits a slower powder to be used, so that the obliged to use telescope sights to avail ball starts more slowly and yet allows the full

ourselves of its full range and accuracy strength of the powder to be used before it

of fire. The accelerating inventions may leaves the barrel, getting a high initial velocity with little recoil, and without "upsetting"

be made use of in artillery, for throwthe ball, as we shall explain farther on. The ing shells, and for siege trains, but promexperiments of the United States government ise nothing for small arins. show that the increasing of the length of the Then, as the secondary point, comes barrel from thirty-three to forty inches (wę, the form of projectile, that in which the speak from memory as to numbers) increased the initial velocity fisty feet per second; but

greatest weight (and thence momentum) this will, in long ranges, be no advantage,

combines with least resistance from the except with such a shape of missile as will atmosphere. In the pursuit of this result maintain a high speed.

every experimenter since the fifteenth † Hunters still dispute as to iron or steel; century has worked. Lautmann, writing and we have used iron barrels made by Amsden, of Saratoga Springs, which for accuracy hollow behind, from a notion that the hol

in 1729, recommends an elliptical missile, and wear were unexceptionable; though gunsmiths generally take less pains with iron

low gathered the explosive force. Robins than steel barrels. But give us steel. recommends elongated balls; and they

« AnteriorContinua »