French
138.6 mm/55 (5.46") Model 1910
Updated 16 May 2006
Used for anti-torpedo boat batteries for capital ships.  The stern guns on the Courbet and Bretagne classes were mounted too low, only 12 feet (3.6 m) above the waterline and were liable to be washed out in even light seas.  They were removed and the ports plated over.  Some of these guns were then used on sloops and in coastal defense batteries.

Of built-up construction with a screw breech and used QF ammunition.
WNFR_134-45_m1912_Provence_pic.jpg

138.6 mm/55 (5.46") Model 1910 guns in casemate mountings on NMN Provence in 1932
Note missing bow casemate guns and the plated in mountings on the stern
WNFR_134-45_m1912_Bretagne_pic.jpg

NMN Bretagne about 1918
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Gun Characteristics
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Designation 138.6 mm/55 (5.46") Model 1910
Ship Class Used On Courbet, Bretagne, Normandie, Lille and Arras Classes
Date Of Design 1910
Date In Service 1913
Gun Weight 11,680 lbs. (5,300 kg)
Gun Length oa N/A
Bore Length about 300.1 in (7.623 m)
Rifling Length N/A
Grooves N/A
Lands N/A
Twist N/A
Chamber Volume N/A
Rate Of Fire about 5 - 6 rounds per minute
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Ammunition
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Type Separate
Projectile Types and Weights SAP - 87.1 lbs. (39.5 kg)
HE - 69.4 lbs. (31.5 kg)
Bursting Charge N/A
Projectile Length SAP - 27.8 in (70.7 cm)
HE - 23.11 in (58.72 cm)
Propellant Charge 23 lbs. (10.4 kg) BM9
Cartridge - 52.07 lbs. (23.62 kg)
Muzzle Velocity SAP:  2,592 fps (790 mps)
HE:  2,756 fps (840 mps)
Working Pressure SAP - 15.1 tons/in2 (2,380 kg/cm2)
HE - 12.7 tons/in2 (2,000 kg/cm2)
Approximate Barrel Life N/A
Ammunition stowage per gun N/A
Note:  The same size cartridge case was used in all 138.6 mm (5.46") guns from the Model 1910 onwards, although the type and quantity of propellant was not always the same.  This allowed obvious advantages in terms of standardization, although much of this was lost by the fact that almost every model used different projectiles.
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Range
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Elevation With 87.1 lbs. (39.5 kg) SAP Shell
Range @ 25 degrees 17,600 yards (16,100 m)
Elevation With 69.4 lbs. (31.5 kg) HE SHell
Range @ 25 degrees 16,500 yards (15,100 m)
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Mount / Turret Data
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Designation Single Casemate Mounts
   Courbet (22), Bretagne (22), Normandie (24) and Lille (24)
Weight N/A
Elevation Originally -7 / +15 degrees, later increased to -7 / +25 degrees
Rate of Elevation N/A
Train About:  +80 / -80 degrees
Rate of Train N/A
Gun Recoil N/A
Loading Angle N/A
Note:  Four, then later eight of these mountings were removed in the early 1930s from the Courbet and Bretagne classes.
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Data from
"Battleships and Battlecruisers 1905 - 1970" by Siegfried Breyer
"Naval Weapons of World War Two" by John Campbell
"Battleships of World War Two" by M.J. Whitley