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PRESENT DAY

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Originally appearing in Volume V17, Page 242 of the 1911 Encyclopedia Britannica.
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PRESENT DAY MACHINE-GUNS Hitherto we have been dealing with weapons worked by hand-power applied to a lever or winch-handle, the motion of this lever being translated by suitable mechanism into those by which the cartridges are loaded, fired, extracted and ejected—the cycle continuing as long as the lever is worked and there are cartridges in the " hoppers " which feed the gun. In the modern " automatic " machine-gun, moreover, the loading, firing, extracting and ejecting are all performed automatically by the gun itself, either by the recoil of its barrel, or by a small portion of the gases of explosion being allowed to escape through a minute hole in the barrel near the muzzle. The following details of the British Maxim, Hotchkiss and Colt types are reproduced from the article " Machine-guns," Ency. Brit. loth ed. The idea of using the recoil, or a portion of the gases of ex- i Attached to the rear of the barrel (b) on either side are two side plosion, for the working of the breech mechani in is by no means plates (h), between which in guides 0 works the aggregation of parts- e D, F, J, K, L, P, T and V, which constitute the lock, and (in bearings) new;- the latter system having been proposed and patented the crank axle E, crank E', and connecting rod I (see figs. 7 to II). (certainly in a very crude and probably unworkable form) by I The connecting rod I joins the lock and crank, being attached to the side levers J of the former by means of the interrupted screw U; the latter enables the lock to be detached and removed. The crank axle E extends through both sides of the breech casing (d), slots.(k, fig. 7), allowing —it a longitudinal movement of about an inch. To its left-hand end, outside the breech casing, is attached the fusee chain Y of the recoil spring X (see dotted lines in fig. 7), and to its right-hand end a bell trunk lever, B B'; the arm B, which terminates in a knob, being turned by the crank handle, the arm B' working against the buffer stop C. In figs. 8, 9 and 11 the breech is shown closed, and it will be noticed that the crank pin I' is above the straight line joining the axis of the barrel, the striker T, and the crank axle E. As the crank is prevented from further movement upwards by the crank handle B taking against the check-lever G (fig. 7), it is clear that the pressure on discharge of the cartridge cannot cause the crank axle to rotate, and so open the breech as shown in figs. to and I2. The withdrawal of the lock and opening of the breech are effected as follows: The total travel in recoil of the barrel is about one inch, but on discharge the barrel, the side plates and lock all recoil together for about a quarter of an inch without any disturbance of the locking as explained above, and by the time this short travel is completed the bullet has left the muzzle. The arm B' of the crank handle then engages the buffer stop C and causes the crank axle E to rotate and the crank E' to fall and so draw back the lock from, and open, the breech. At the same time the fusee chain Y is wound up round the left-hand end of the crank axle E and the spring X extended. In the meantime the knob of the buffer handle B swings over, and just as the lock reaches its rearmost position (as in figs. to and I2) strikes the flat buffer spring H, and, rebounding, assists the crank in revolving in the reverse direction; the spring X also contracts, and, unwinding the fusee chain, draws back the lock again and closes the breech, a fresh cartridge having been placed in the barrel as explained below. The gun is fired by means of the trigger F, which is actuated b--the-projection (l) on the trigger bar (S), the latter being drawn bac~C when the button (m) on the push lever (n) is pressed forwards. If, therefore, the button he kept permanently pressed, the projection (l) will always lie in the path of the trigger F just as the lock reaches its forward position and the breech is closed, and the gun will fire museums, there can be no doubt that (Sir) Hiram S. Maxim was the first to produce a finished automatic gun of practical value. His patents in connexion with this particular class of weapon date back to 1884, and his gun on the recoil system was, after extensive trials, adopted into the British army in 1889 and into the navy in 1892. It is very possible that Bessemer's idea did not bear fruit earlier because the fouling left by the old forms of " black " or smoky powders was apt to clog the moving parts and to choke any small port. With modern smokeless powders this difficulty does not arise. The Maxim gun,i as will be seen from figs. 7 and 8, consists of two parts, the barrel casing (a) and breech casing (d), secured firmly maxim together. The former (a), which is cylindrical in form, Gus-. contains the barrel (b), and the water surrounding it to keep down the very high temperature attained by rapid fire, and the steam tube (c), which by the action of a sliding valve allows of the escape of steam but not of water. The barrel has asbestos packings at its front and rear bearings in the casing, which -b:caa¢{ B
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