92 on the Principal Constructions Of

92 ON THE PRINCIPAL CONSTRUCTIONS OF BREECH -LOADING MECHANISM FOR SMALL ARMS, AND THEIR RELATIVE. MECHANICAL ADVANTAGES. BY MR. WILLIAM P. MARSHALL. The general adoption of Breech-Loading Small Aims that has now taken place has caused a number of mechanical contrivances to be brought out, of great ingenuity and interest, for overcoming the difficulties met with in obtaining a satisfactory breech-loading action. The objects to be effected are-lst, to open the breech of the gun and close it again rapidly and securely by a simple and convenient movement, without removing the hand far from the trigger, and without shifting the hold of the gun by the other hand ; %id, to extract the empty cartridge-case of the previous charge by the same movement as that which opens the breech, so as to present the open barrel ready for instant re-loading; and 3rd, to have the whole mechanism of a simple, strong, and durable character, free from risk of derangement either by accident, long wear and tear, rough usage in active service, exposure to wet or sand, or fouling from long continued firing. In the case of military guns the latter requirements are of special importance, as the whole value of a breech-loading gun in increased rapidity of fire would be outweighed by any increased liability to failure in action. When the formidable and conflicting Tharacter of these requirements is considered, it will be seen how much mechanical credit is involved in the very complete and successful manner in which they have now been met. Breech-loading guns were first adopted by the Prussian army, in which the celebrated Needle-gun has now been in use for more than twenty years, and for many years has been the universal arm there used ; but the introduction of the principle into other countries is only of recent date, and in this country, although breech-loaders BREECH-LOADING RIFLES. 93 have for fourteen years been in use to a limited extent for the cavalry carbines, it is only within the last five years that the principle has been adopted for the army generally. In the case of the cavalry carbines, breech-loading was adopted solely for the purpose of overcoming the difficulty of loading whilst on horseback the muzzle-loading rifles then in general use for the army, in which the charge had to be driven home by the ramrod in loading. The breech-loading action then adopted for the purpose was required by the military authorities to fire a paper cartridge, ignited by the ordinary percussion cap, which had to be put on for each charge, involving the consequent loss of time and inconvenience in loading. A great objection was felt at that time by the military authorities of this country to any considerable increase in the facility for rapidity of fire, on the ground of a supposed risk of ammunition being wasted by too rapid firing before the men came within effective range, leaving them then unduly short of ammunition. The extension of breech-loaders for military purposes was consequently checked in this country for many years, although the principle came into universal use for sporting purposes on account of the great advantages experienced in convenience of loading and rapidity of fire. But the continued experience of the Prussian needle-gun proved conclusively that the objection of risk of wasting ammunition had no real foundation, and that with men properly trained to the use of breech-loaders there was no more risk of ammunition being wasted with them than with any other gun ; whilst on the other hand the overpowering command given by the great increase in rapidity of fire made it a case of simple necessity for all other troops to be armed also with breech-loaders, in order to prevent their being placed under a heavy disadvantage. With the use of breech-loaders it has been found that each man is enabled to fire about ten shots whilst advancing from 400 yards to 200 yards range, each shot being fired with defi,nite aim from the knee, and 45 per cent. of the shots hitting a target of 6 feet height and 2 feet width. Troops armed with muzzle-loaders would be at a heavy disadvantage opposed to {ucha force j and the great power of defence given by breech-loaders tgainst approaching cavalry renders an attack impracticable on open 94 BREECH-LOADING RIFLES. grouud, the infantry being enabled to fire as many as twelve volleys during the time of the cavalry approaching after having come within range. Several distinct principles of action have been followed in the different constructions of breech-loading mechanism, the main object in each being to provide the means of rapidly opening the breech and loading the gun, and then closing the breech again so as to resist securely the force of the explosion in firing. The first principle tried was that of the celebrated Prussian 'Needle-gun, shown in Figs. 1to 6, Plates 21 and 22, in which the breech is opened by drawing back a bolt B in a line with the barrel, and the front end of the bolt forms a conical cup that closes the breech, when pressed home by turning the handle of the bolt down on one side into an inclined catch. The explosion of the cartridge C is effected by a steel needle N, Fig. 1, which is driven forwards by a spiral spring, and piercing the base of the paper cartridge passes through the powder, and st,rikes the fulminate inside a cap situated within the cartridge and immediately behind the bullet, as shown in Fig. 3. The base of the bullet is fitted into a sabot made of compressed paper, which is forced into the grooves of the ri%e by the discharge, and causes the bullet to rotate with it. The spiral spring and needle-carrier A are contained in a tube D which slides within another longitudinal tube B ; and this outer tube has also an independent longitudinal sliding movement, and forms a long bolt with a knob handle projecting at the side, as in Figs. 1to 4. The first action in loading the gun is to withdraw the needle from the barrel by means of the thumb-piece E in the rear of the lock, as shown in Fig. 1, pressing at the same time on tt spring-catch F, which requires releasing to allow of the withdrawal. The second action is to draw back the bolt B, carrying the needle and spring within it, as in Figs. 1 and 2, thus opening the breech; the bolt handle is first struck upwards into the position shown in Fig. 2, so as to release it from the side catch into which it fits when the breech is closed. The third action is to insert a fresh cartridge into the barrel through the opened breech, as in Fig. 1. The fourth action is to close the BREECH-LOADINQ RIFLES. 95 breech again, by pushing the bolt forwards into its first position, as in Fig. 5, turning the handle down sideways to lock the bolt, as in Fig. 4. The fifth action is cocking the gun by pushing in the end thumb-piece E to its original position, as in Fig. 6, in which it is then retained by the spring-catch F; this compresses the spiral spring, as the shoulder on the needle-holder A is held fast by the trigger-catch I, which allows it to pass backwards when the sliding bolt B is withdrawn, as in Fig. 1, but catches and detains the needle-holder when the bolt is pushed forwards again for closing the breech, as in Figs. 5 and 6. The end thumb-piece E, when pushed forwards for cocking the gun, enters a slot in the back end of the sliding bolt, as in Fig. 6, and holds it from turning, thus preventing any possibility of the breech being opened while the gun remains cocked. The sixth action is firing the gun by pulling the trigger T, which releases the needle-holder A and allows it to be driven forwards by the compressed spring, as in Fig. 3. This Needle-gun was invented in an imperfect form more than forty years since by J. N. Dreyse, a gunmaker of Somerda in Prussia; and after a long series of experiments with the aid of the Prussian government it was brought to its present form, and has been adopted generally for the Prussian army for the last twenty years. At the commencement of that period the arm generally in use in this country and elsewhere was the old smooth-bore musket, until the invention shortly afterwards of the Mini6 expanding bullet, which allowed of the general use of rifled barrels for muzzle-loaders. In the Prussian needle-gun the means of closing the breech so as to prevent the escape of gas backwards from the barrel at the moment of firing is by a conical cup at the front end of the sliding bolt, which fits over a corresponding conical end of the barrel, as shown at G in Figs. 3 and 5, and is forced into close contact by the slightly inclined face of the catch into which the handle of the bolt is pressed when turned down sideways, as in Fig. 4. In practice however it is found that this joint is not sufficiently tight tfo prevent the occurrence of a ‘‘ spitting ” or escape of gas into the face of the firer, which becomes inconveniently great after a long continued use of the gun.

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