Gun-car′riage.
The apparatus upon which a cannon is mounted for service.
It may or may not be adapted for the transportation of the piece.
The first consisted merely of a timber-block, or frame, to which the cannon was secured by straps or bolts.
Uprights, with holes for pegs, were sometimes employed to give elevation to the muzzle.
Afterwards a species of trough, having a butt-piece and mounted on wheels, was introduced (
A, Fig. 2339). Subsequent improvements brought them nearly to the form
B, which represents a carriage of the Gribeauval pattern.
Gribeauval, a French artillery officer, made great improvements, 1765, in gun-carriages and the organization of artillery, reducing the size of the parts, and making the similar parts, for those of the same class, interchangeable; he also added a tongue, so that two horses could draw abreast, and made the limbers so that one sort would answer for several different kinds of carriages.
Land gun-carriages comprise field, siege, casemate, and barbette carriages.
The two former are adapted for the transportation as well as service of the piece, while the latter are intended to be kept in one position in a fortification.
A smaller kind of field-carriage may be readily taken to pieces and put together, so as to be carried on mules' backs in a rugged and mountainous country.
Field-carriages include those which are adapted to accompany the movements of troops during an engagement, and carrying a class of guns weighing from 800 to 1200 pounds, as the 12-pounder smoothbore and lighter rifled cannon.
These carriages are known as “stocktrail” pattern, from having a single piece, which serves as the trail, inserted between the two cheeks on which the trunnions rest.
The
Gribeauval and older patterns of carriage had no stock, the ends of the cheeks resting immediately on the ground; the fore-wheels were also smaller than the hinder.
C is an elevation of a field-gun carriage without its limber.
The various parts are, —
 |
|
Field-gun carriage. |
| A, stock. | i, stop for rammer-head. |
| B, cheek. | k, ear-plate for worm. |
| a, lunette. | l, elevating-screw. |
| b, trail-plate. | m, under-strap. |
| c c, pointing rings. | n, implement-hook. |
| d, handle. | o, D-ring for hand-spike. |
| e c, prolonge hooks. | q, trunnion-plate. |
| f, wheel-guard plate. | r, cap-square. |
| g, lock chain, bolt, nut, and washer. | s, cap-square chains and keys. |
| h, turn-buckle, chain, and | 1, prolonge. |
| hasp for sponge and | 2, sponge and rammer. |
| rammer. | 3, hand-spike. |
The detachable forepart of the carriage is called the limber.
It carries a chest for containing ammunition, upon which the cannoniers sit. The limbers for all field-carriages differ only in the interior fitting up of the chest, adapting it for receiving different kinds of ammunition.
A
caisson for carrying ammunition accompanies each field-piece.
This vehicle has a limber similar to that of the gun-carriage.
Its rear part, or body, carries two ammunition-chests, the three, with that on the carriage-limber, containing the full supply of ammunition for the piece.
Each field-battery of four or more pieces is also accompanied by a
traveling-forge and a
battery-wagon,
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which contain the necessary tools and materials for ordinary repairs.
Each carriage is drawn by six horses, harnessed in a manner somewhat different from the ordinary way, the traces of the wheel horses being directly attached to the splinter-bar of the limber, and the traces of the leaders connected to those of the wheelthe breech supported on the bolster
u. The small parts for holding the implements are wanting.
 |
|
Siege-gun carriage. |
Three sizes are employed in the United States artillery service, one for the 4 1/2-inch rifled gun, one for the 18-pounder smooth bore and 30-pounder rifled gun, and one for the 24-pounder and 8-inch howitzer.
Barbette carriages are intended for firing over the parapet of a fortification, and are adapted to mount guns of 32-pounder, 8-inch, 10-inch, 15-inch, and 20-inch caliber.
The carriage proper rests on a frame called the
chassis, which turns about a fixed pintle, so that it may be traversed to point wholly or partially around the circle.
See barbette.
Casemate carriages resemble the above in their general construction, but are somewhat less high in proportion.
They are placed in casemates, where the gun is fired through an embrasure.
See casemate.
These two latter classes of carriages, and also mortar beds, have since 1860 been made of wroughtiron, which material has also been tried to some extent for field-carriages with a promise of good results.
Cast-iron was at one time tried and found utterly unsuitable.
Ordinary broadside naval gun-carriages much resemble the army casemate carriage, but have no chassis.
They are mounted upon four small wheels, called “trucks,” and are run in and out and pointed by means of two
side tackles, hooked respectively on the left and right to the side of the ship, and a
traintackle hooked to a ring-holt behind the carriage.
Excessive recoil is checked by the breeching, a stout rope passing through a hole in the cascabel of the gun, and shackled to the ship's ribs on either side.
Elevation is given either by means of a graduated quoin or an elevating screw.
In the
Marsilly carriage the two front rollers are wanting, the front transom resting immediately on the deck.
Light broadside guns and boat guns have their carriages arranged to run on slides corresponding to a chassis, and have compressors for moderating the recoil.
Boat guns are also provided with field-carriages of iron in order that they may be employed on shore.
Heavy pivot guns as 11-inch, on upper decks, are mounted on a peculiar carriage, which enables horses.
Swingletrees and whiffletrees are thus dispensed with.
The siege-carriage (
Fig. 2340), though larger and heavier than that for field service, differs little from it in general construction.
For transportation the gun is moved backward, the trunnions resting against the head of the traveling trunnion-bolt
t, them to be directed to any point around the circle by means of side tackles and
in and
out tackles hooked to bolts appropriately placed around the deck.
Very heavy guns, as 15-inch or 20-inch, being always placed in revolving turrets, their carriages need have no lateral motion, as this is obtained by the rotation of the turret itself, operated by connection with the engine of the ship.
Devices similarly operated are also provided for loading.
See Batteryforge, battery-wagon, caisson, barbette-carriage, casemate-carriage, mortar.
The necessities of modern warfare, land and marine, have given rise to many inventions for operating heavy guns and for the protection of those working them.
For the latter purpose, besides mantelets and shields, arrangements have been made for rotating the turret in which the gun is mounted so as to cover the embrasure; depressing the gun during loading below the embrasure, etc.
For counterpoise carriages see: —
Brewer's gun-carriage, 1870, is supported on a platform which is supported by levers within a curb, and a weight suspended from the ends of the levers counterpoises the gun, carriage, chassis, and platform.
Callender and
Northrup, 1864, have a platform supported by a piston in an air-cylinder beneath.
Eads (1865, 1869, and 1871) causes the recoil of the gun to depress it backwardly and downwardly, it being poised on its trunnions on the end of an arm which oscillates in an are. As the gun descends, a piston traverses in a cylinder, compressing air therein, and the elasticity of the air assists in restoring the gun to its position when the loading is complete.
Coughlan, 1870, has a cogged segment and weighted toggle which allow the gun to depress by the force of recoil.
Taggart, 1863, has two guns on a cylindrical carriage which is on an axis reaching athwart the vessel.
The gun beneath is in loading position below decks, while the one above is in firing position.
The latter being fired, the axis is rotated and the guns change places.
Winans, 1865, lifts his gun, carriage, and traverse into firing position by steam piston and cylinder beneath.
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Houel and Caillet have a system of levers which oscillate backwardly by the recoil, and in so doing bring into action a spring which afterward assists in restoring the gun to firing position.
See also
Coon, 1863;
Foster, 1869.
Wappich, 1863, has a toggle-joint and screw for elevation and depression.
Also screws beneath the trunnions.
In
Moncrieff's gun-carriage (
Fig. 2341) the gun is supported upon a moving fulcrum, which, on the firing of the gun, is caused to shift nearer to the gun and farther from a counterweight, spring, or other force, while at the same time the gun is brought into a lowered position for reloading, and is then automatically raised into position for firing.
By the shifting of the fulcrum, the statical momentum of the balance weight is made to preponderate so greatly over that of the gun that it will, when allowed free action, after the loading of the gun, raise the same into its original position.
For running the gun in and out of battery, and traversing and operating guns in turrets, see patent of
Ericsson, 1866, 1870;
Perley, 1865, 1867;
Eads, 1864, 1865;
Bartol, 1863.
Training twin guns in parallelism in turrets,
Eads, 1866.
Eads, 1864, 1865, has a means for training the gun upon an imaginary center, which is the center of the exterior opening of the port or embrasure, so as to reduce the opening to the smallest size.
