GUNS. Cannon for firing at moving objects and for delivering a heavy fire at critical periods of an engagement. The de sired rapidity of fire is obtained by using fixed ammunition; that is, ammunition in which the projectile and charge are put up in one piece. After the limit of size for machine-gun action had been reached the advantages of rapid fire to guns of calibres large enough to be effective against torpedo boats was appreciated. and 3-pounders, and then 6-pounders were made by Hotchkiss and Nordenfelt, with one barrel and worked by hand, but with quick-opening mechanism and fixed ammunition. This movement progressed and de veloped to a remarkable extent between 1890 and 1900, heavier and heavier guns being required as torpedo boats increased in size and protection to their boilers (by coal, ete.)—the limit being the weight of charge conveniently handled as one piece, about 5 inches calibre.
The development of rapid-fire guns may be said to date from toward the end of the year 1881, when the British Admiralty advertised for designs of a gun that should fulfill the follow ing requirements, viz: The weight of the gun and mount not to exceed ten hundredweight (1120 pounds) ; the projectile to weigh 6 pounds and have a muzzle velocity of not less than 1800 feet per second; the projectile and powder to be made up in one cartridge; the service of the gun to require not more than three men; under the aliove•mentioncd conditions, the gun to be capable of firing at least twelve aimed shots per minute. About the same time the French Department of Marine invited designs for a 3-pounder to fulfill relatively the same conditions. These two advertisements resulted in the pro duction of the rapid-fire gun. Mr. Hotch kiss, an American who had established works in France, brought out a series of guns, I, 3, and 6 'pounders, and it is per haps interesting to learn that the first order placed with him was from the United States Navy Department. Mr. Nordenfeldt brought out similar guns in England. The 3-pounder and 6-pounder rapid-fire guns advertised for by France and Great Britain were intended for use against torpedo boats, and it was consid ered that the calibres selected were amply large. Later experience has modified this view, but it must be remembered that the torpedo boats of 1881 were small, slow, and weak. Rapid-firing guns soon began to increase in size. In a short time the calibre of 6 inches was reached. but the fixed ammunition was found to lie un wieldy and easily sprung out of shape. The next step was the separation of the projectile and powder in the larger guns, but retaining the brass case for inelosing the powder charge. The speed of fire in these guns was not
reduced by the change, as the separate parts of the ammunition were more easily and rapidly handled.
In 1997 Messrs. Vickers Sons & Company brought out a new type in which no powder case tion at the same time. The system was almost im mediately adopted for use in the new guns of the United States Navy, and it bids fair to be univer sally accepted for guns of 5-inch calibre and over.
The increased speed of fire in the intermediate ealibres naturally led to a general improvement in the loading mechanism of all guns, and it is now safe to say that the rate of fire of large guns has been doubled in the past four or five years and gains are constantly being made. Krupp brought out what he called a 24-eenti meter (9.45-ineh) gun four or live years ago and in 1900 a 'rapid-fire' 28-eentimeter piece, but they are not faster working than the new pieces of like calibre in the United States, British, and is used. The breech mechanism is of the rapid working type and the obturation (i.e. the pre vention of escape gas to the rear) is effected by means of a modified form of the Dc Range gas cheek. (See GUNS, NAVAL) . The primer is eject ed automatically when the breech is opened and a loading tray is automatically drawn up in posi Freneh navies. Krupp's nomenclature was so obviously misleading that ninny officers are now avoiding the use of the expression In the United States Navy the terms gun and gun are now officially defined as follows: (a) "A gun is one that has a quick-working system of breech closure operated by a single throw of a lever or crank; uses either fixed or separate ammunition, but, when using the latter. requires the powder charge to be put up in a metallic cartridge case." (b) "A gun is one that has a quick-working system of breech closure, operated by a single throw of a lever or crank, is fitted with an auto matic lock, and uses separate ammunition with mechanisms; Austria uses Skoda and Krupp mechanisms; the Nordenfeldt (except the Maxim Nordenfeldt) is not much used in any naval service, and the Bofors is found chiefly in the the powder charge put up in a cartridge bag." These definitions are purely arbitrary, are used only in the United States Navy, and were decided upon solely as a matter of convenience. There was no hesitation in adopting the terms, as the nomenclature of rapid-firing weapons was in so chaotic a state that any authoritative change was an improvement. The terms rapid-fire in the United States and quick-fire in England had hitherto been synonymous.