Schneider-Canet 47mm light QF gun M. 1898
The Schneider-Canet 47mm L/60 gun was built throughout of steel, and it was formed of four parts:
a. the inside tube which run the whole length of the bore, and bore in the rear against a projection of the jacket;
b. the jacket, in which was cut the breach seating, and which was provided in the rear with a coil made with lugs for fixing the brake and recuperator rods;
c. the front coil, which joined the gun tube to the jacket;
d. the breech mechanism, of the concentric-threaded type, with a extra quick-opening action.
The mounting consisted of the bedplate bolted on the deck; the movable slide that rested on the bedplate, with the interposition of a pivot; the oscillating housing, or jacket, which carried the gun, and rested in the slide. The slide, the housing, and the gun turned in two guiding collars with a vertical axis, for training the gun. The housing and gun oscillated around the housing trunnions, for obteining the required elevation.
The bedplate was in the shape of a truncated cone, and consisted of the outside envelope of wrought steel, fitted at its lower part forming a flange, by which the cone was bolted to the firing platform; of the inside gun-metal body, on which were fitted:
a. the top plate, which carried part of the weight of the mechanism;
b. the two guide collars of the slide pivot, joined together by a piece in the shape of a truncated cone, provided with stiffening ribs.
The slide was in one piece, and rested on the bedplate. It consisted of:
a. two parallel cheks with trunnion plates that received the trunnions of the gun-housing; on one side was a projection in which engaged a square-headed bolt that served to fix the trunnion at any required elevation;
b. a disc which joined the two checks at their lower part, and carried the buffers that limited the degree of elevation of the gun;
c. the central pivot, formed of two cylindrical parts, joined together by a truncated cone.
At the lower part of the pivot was a bolt provided with a catch. When the slide was in its place, a nut was screwed on the bolt, which beared on the bottom of the pivot and prevented all raising during the fire. Besides this, a handscrew went through the shell in the bedplate, and by bearing against the body of the pivot, allowed of fixing the gun in any position.
The housing was cylindrical and sourrounded the gun so as to form a slide during recoil and running out. It consisted of :
a. a jacket with trunnions, and fitted at the ends with gun-metal rings to insure perfect guiding;
b. a recoil cylinder in one piece with the jacket, and on one of the ends of which was screwed the central counter-rod.
On the left side of the housing, there were two bearings on which were bolted the flanges that held the recuperator and the butt-end for training of the gun. The hydraulic recoil cylinder was on the Schneider-Canet system, with central counter-rod; its rod was held by a nut in the lower projection of the recoil rear jacket. The recuperator consisted of a cylindrical chest containing a series of spiral springs; its governing rod was fixed to the second projection of the recoil rear jackey, and was provided with a bearing ring which weighed on the set of springs. The working of the recoil cylinder was therefore quite indipendent of that of the recuperator, as these elements were without inside communication from one to another; they acted separately during recoil, the recuperator alone effecting the running out of the gun.
The various parts of the mounting being of comparatively small weight, and the shifting of the movable parts requiring but a little effort, training and elevation were secured by the gunner bearing with his shoulder on the butt. By taking hold of a suitable handle in one piece with the butt, the gunner had no difficult in sighting the target accurately.
When a quick-firing salute was to be effected without any modification in the sighting of the gun, it sufficed to set the screw on the right-hand trunnion in order to fix the gun in the required position. The scale was carried in a slide which formed part of the jacket, and the sight was on the left trunnion. A suitable shield protected the gunners and the working part of the gun.
SOURCE : DREDGE. James: The Works of Messrs. Schneider and Co.