138.6-MILLIMETRE AND
14-CENTIMETRE GUNS.
183
138.6-Millimetre (5.456-In.) Gun on Muzzle-Pivoted
Mounting (Fig. 600).—Guns of this type have been
supplied to the French Navy.
Weight of gun
,, mounting
,, projectile
,, charge (prismatic brown puwder)
Muzzle velocity ...
Angles of elevation _______________
3250 kg.
2870 kg.
30 kg.
12.3 kg.
590 m.
+ 28 deg.
— 12 deg.
7150 Ib.
6314 Ib.
66 Ib.
27 Ib.
1935 ft.
+ 28 deg.
— 12 deg.
slide is formed of two parallel guide beams carried on
conical rollers, which run on the roller paths. The gun-
carriage proper rests, through cylindrical rollers, on the
inclined girders of the slide. Under these is placed the
hydraulic recoil cylinder that checks the recoil of the
system.
A pinion with helical gearing that Works on a toothed
sector, fitted to the gun, serves for obtaining the required
elevation, while the gun is trained by a handwheel and
Fig. 599. 12-Centimetre Gun and Mounting (43 Calibre) ; Model, 1890.
Fig. 600. 138.6-Millimetre Gun and Muzzle-Pivot Mounting.
The breech-block is cylindrical with interrupted tlireads,
and slides in a bracket which turns round a vertical hinge ;
it is worked by a jointed lever. A plastic obturator is
placed between the bulb of the movable head and the front
end of the screw. The striker can only act when the
breech is completely closed.
The mounting consista of the bolster, the slide, and the |
carriage. To the bolster are connectée! the muzzle pivot, j
and concentric roller paths bolted to the deck. The inclined !
toothed gearing which acts on a circular rack fitted
to the bolster. The recoil cylinder is on the hydraulic
system, with constant volume and loaded valves. The
force of the recoil is utilised to bring the gun back into
battery.
14-Centimetre (5.51 i-In.) Gun on Central-Pivoting
Mounting (Figs. 601 and 602).—Guns of this type have
been. supplied to the Spanish Navy.
The breech-closing mechanism is essentially similar in
2r