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rounded angles, slightly varying in form (see fig. 72 a b), and the other five (fig. 74). These are respectively the
plans of Major Nuthall and Mr. Boucher; but the latter having published full particulars in the Field of May 14th, 1859, (while Major Nuthall's was not patented for some time afterwards,) he is entitled to the priority in the merit of the invention if the two prove to be similar in all other respects, as I believe they are. Mr. Boucher also specially alludes to the four-sided plan with an unfavourable mention; but, to avoid any risk of mis-statement on my side, I will give his letter entire, as far as it relates to this subject :
" Surrey Villas, Camberwell. “I am an advocate for a somewhat heavy rifle, as the shooting with such a weapon is always more steady, with less recoil ; particularly if the weight of the metal is judiciously accumulated behind and immediately surrounding the breech. The barrel of the one I am now about to describe is 2 ft. 6 in. in length ; weight, 54 lbs. The bore is exactly half an inch in diameter—a size which the great majority of our practical marksmen agree now in recommending I am not favourable to four grooves, for this reason : when the bullet leaves the muzzle of the piece, it is made by the force of the explosion nearly square, or four
sided, especially if the grooves are deep, causing a considerable amount of extra friction, and consequently retardation by its grinding motion, while passing through the air. I have therefore fixed on five, though, from my style of grooving, many have supposed the barrel to be a smoothbore.
“ In order to understand the mode of grooving thoroughly, I must ask the reader to draw for himself, on as large a scale as he pleases for the sake of distinctness, the geometrical figure called a pentagon. Then, in the centre, let him draw a circle, so that its edges may just touch the sides of the figure. This circle is to represent the end of the bullet. The next process is to round off the angles of the figure to rather less than a third of their original depth, when they will appear to be broad, shallow grooves, somewhat like the second diagram above; the first diagram representing the figure before the angles were rounded off.
"The twist of the spiral is at the rate of one turn in five feet, which generates a rotary motion quite sufficient for a range of one mile, for, as there is little friction, comparatively speaking, to retard the progress of the bullet in the barrel, it proceeds with greater velocity after leaving the muzzle, thus rendering a less amount of twist necessary than in a barrel having more friction.
“ Taking into consideration all the experiments I have made myself, all I have witnessed in other quarters, and all the experimental reports I have read on the subject, this is the mode of grooving which I still prefer, and which I recommended to our authorities in the autumn of 1853, and again in 1855. I have loaded and fired hundreds of rounds from such a barrel without the slightest trouble, the last bullet going down as easily as the first; in fact, a glance at the diagram will show any man conversant with the subject that there can be no friction that cannot be overcome by merely pressing the ramrod gently and steadily down, so that the shape of the bullet cannot be destroyed, nor the powder caked, by the bullet being jammed down upon it.
"This mode of grooving requires only attention on the part of the workman, without which any sort of grooving becomes worse than useless, disappointing and deceiving the man who
pays a high price for a showy and, said to be, superior weapon. The cutter should be just a fifth of the circumference of the bore, and very shallow, and care taken not to go so deep as to affect the five points of the original surface where the bullet is seen to touch the sides, leaving the bore without any sharp edges. I have enclosed you a bit of lead, which I have driven into the barrel; you will feel, by rubbing your fingers over it, that it is nearly smooth, though on looking at the end you will at once perceive the mark of the five hollows or grooves that grasp and guide the bullet while turning and passing through the barrel.
“My “disc bullet'—the one I recommend for such a barrel—is what is commonly called Cylindro-conoidal in its outward form. That which I generally use is about 1 1-16 inches in length, as represented by the diagram; though it may be made longer if the rifleman desires a heavier one for particular purposes.
“ In the end of the bullet, which is a fair cylinder for half its length, I have a cavity formed as shown at a, which extends a little more than half the length of the bullet. Upon the edge of the cavity bb I place the round disc c, which is cut out of thin iron to fit exactly, so that it will not drop out after it has been pressed in by the thumb or gently on a table. When the explosion takes place, the disc becomes so firmly fixed by the contraction of the lead around it that it never falls out, nor is it driven, or intended to be driven, further in than the rest of the lead at the base of the bullet.
“ Experience shows that the disc' bullet rifles itself as distinctly as if it had been cast in the grooves of the barrel: a complete answer to the supposed effects of all such nonsense as the expanding' cups and plugs which many, who ought to know better, still believe in. It may also be called a safe bullet, for any number may be fired at a distant object over the heads of bodies of men employed or moving in the intermediate space, without any fear of the discs leaving the bullets, like the cups of the Minié,' and injuring the men. I have fired thousands of these bullets, and, though not a first-rate marksman, I have repeatedly placed 70 per cent. of them in a space two feet broad by four feet high, at 600
yards distance. This can be corroborated by unquestionable authority.
“Mr. Greenfield, of Broad-street, Golden-square, has been in the habit of making my bullet-moulds, and, as my object is to encourage rifle-shooting, he has full permission from me to make moulds of this pattern for any gentleman applying for the same. In giving the order, however, I would recommend the barrel to be given to him, with instructions to make the bullet large enough just to touch its sides, but to fall to the bottom by its own weight. My reason for advising this is, that I never use paper or patch, but simply dip the bullet half way in a very hot mixture of two parts bees’-wax, one part soft-soap, and one part tallow or hogs’ lard, the refuse being previously carefully skimmed off. I generally mix a few pounds of these ingredients together at once, as it has then only to be made thoroughly hot and liquid for use at any time afterwards.
“Some years ago, when carrying on an extensive course of experiments, with bullets of various sizes and forms—some with paper wrapped round them like the Service ammunition, some with patches, and others in a naked state—I became so satisfied of the superiority of the ‘naked' bullet, and its simplicity in loading, over other methods, that I have continued ever since to use such for my own private shooting. Our most scientific military authorities have also lately declared themselves in favour of this system. One says: The employment of a naked bullet, thus doing away with that interfering medium, the paper, will be a matter of great importance if we can succeed.' Another says: 'I entirely concur in what has been said as to the advantages to be derived from the naked bullet in preference to one with paper; it is evident that the naked bullet properly supplied with grease will fill the grooves of the rifle better than one which has the intervening substance of paper around it.' A third adds : ‘In my opinion it is to the paper alone the defects in fouling and accuracy are attributable; bullets have lately been constructed and used without paper, and the result has been that these bullets have not only shown themselves superior to the plug, but barrels which would have been rejected with the latter as bad barrels have produced greater accuracy than has ever been obtained with the plug ammunition. These are the opinions of officers of high standing, who have devoted much time to the study of rifled arms, and are therefore worthy of every consideration.
“In my next I purpose giving a description of some other contrivances, which I consider improvements, together with a few remarks in connexion with their use. I shall also be happy to answer any questions on the subject of rifleshooting, if space is granted me for that purpose; but, as I shall endeavour to give scientific reasons for everything I say or advise, I trust that those who may be disposed to differ from me will do the same; thus placing it within the power of many of your inquiring readers to judge and decide for themselves.
“J. BOUCHER.” On the other hand, Major Nuthall's grooving is represented in the annexed section, the original of which was kindly furnished me by himself. The rifles on this plan have been used with his own bullet, which has a very wide cannelure, and also with the regulation ball, but as far as I know, without any very great advantage in point of accuracy. Mr. Boucher’s I have not seen shot, but I am assured by those who have that the performance, at all practicable distances, is quite equal to his own description.
THE WHITWORTH RIFLE. Seventhly, we have the hexagonal bore of Whitworth, which has attracted a great deal of attention, and which, when carefully made, is capable of effecting excellent shooting. But if the ball used is also pentagonal, as recommended by Mr. Whitworth, it fits into the angles so accurately, that the
slightest amount of foulFigs.
ing interferes with the
loading. Fig. 75 shows b
the shape of the ball and a section of the barrel,
which also represents the WHITWorth's BALL AND RIFLE.
transverse section of the