10.5 cm fortress guns
The 105mm artillery fortress of the Swiss Army were in the Swiss fortifications of the Second World War built.
history
A special weapon worth mentioning here is the 10.5 cm turret cannon , which is dealt with in a separate article. The rest of the listed guns are fortress guns for a minimal notch opening ( minimal notch ). This means that the opening in the notch is just big enough for the gun barrel to fit through.
These 10.5 cm cannons and howitzers were mostly built into rock works. In areas where there were no rocks, open-cast bunkers were also created. The positions in Faulensee and Jaunpass are striking examples .
Not all fortresses were equipped with the above guns from the start. Some of the fortresses were armored with field artillery guns. This was primarily due to the lack of special bunker weapons or the 12 cm field howitzers , which were already older in the mid-1940s, were installed. Systems that were planned for armoring with guns of the field artillery can usually still be recognized today by the rather wide tunnels that were necessary so that the guns on the field mounts could be driven into the gun stands. All field guns were replaced by permanently installed guns on lever or stand mounts by the end of the Second World War.
Types
These are cannons and howitzers of the following types:
- 10.5 cm L42 cannon on a stand mount
- 10.5 cm L42 cannon on a lever mount
- 10.5 cm L52 anti-tank cannon on a lever mount
- 10.5 cm L22 howitzer on a lever mount
- 10.5 cm turret cannon
10.5 cm L42 cannon on a stand mount
Procurement of the 10.5 cm cannon was decided in 1934. The first guns were supplied by the Swedish company Bofors. The guns were then manufactured under license by K + W in Thun. The Bofors gun had a perforated muzzle brake, which was replaced by K + W Thun with a two-chamber muzzle brake. The designation of the gun is: 10.5 cm Fest Kan 39 L42.
Main ingredients
The main components of the gun are:
- Tube with bottom piece and closure
- Cradle with reverse brake and hauler
- Alignment attachment
Technical specifications
-
Tube: caliber 10.5 cm
- Length (without muzzle brake) 4410 mm (42 caliber lengths )
- Twist, right-handed, constant
- Closure: horizontal wedge closure
- Return brake: hydraulic
- Catcher: hydro-pneumatic
- Return: variable, maximum permitted 850 mm
-
Parallel lever mount:
- Field of view: ± 533 artillery per mill
- Elevation field : −17 to 787 radius per mill
Stand mount
With the stand mount, most of the tube is in the bunker. Only the front part protrudes from the notch opening into the open. This has the advantage that the gun barrel is well protected from external influences. A disadvantage of this system is that the shutter cannot or can hardly be reached at low elevation without aids for the loader.
The mount consists of a base plate and a stand. The stand is guided on the circular scenes of the base plate. The centers of the circular guide carriages of the base plate and stand are arranged in such a way that the fictitious pivot point of the pipe lies in the outlet opening of the armor plate. At the upper end, the stand is guided through a drawbar by means of a cat in the circular segment of the casing. To reduce friction, the stand rolls on adjustable spring-loaded ball bearings on the cheeks of the base plate.
Straightening gear
There are two straightening gears attached to the stand on both sides.
- Side straightening gear
- Elevation gear
Loading platform
The loading platform is used to facilitate loading at small elevations . In the case of small pipe inclinations, the base piece with lock is at a height that cannot be operated from the floor. The loading platform frame is suspended from the ceiling on rails and firmly connected to the stand by a railing. At a distance / elevation of more than 1,600 artillery bullets, the two platforms are unfolded and the gun is operated from the ground.
10.5 cm L42 cannon on a lever mount
Procurement of the 10.5 cm cannon was decided in 1934. The first guns were supplied by the Swedish company Bofors. The guns were then manufactured under license by K + W in Thun. The Bofors gun had a perforated muzzle brake, which was replaced by the K + W Thun with a two-chamber muzzle brake. The designation of the gun is: 10.5 cm Fest Kan 35 L42
Main ingredients
The main components of the gun are:
- Tube with bottom piece and closure
- Cradle with reverse brake and hauler
- Alignment attachment
Technical specifications
-
Tube: caliber 10.5 cm
- Length (without muzzle brake) 4410 mm (42 caliber lengths )
- Twist, right-handed, constant
- Closure: horizontal wedge closure
- Return brake: hydraulic
- Catcher: hydro-pneumatic
- Return: variable, maximum permissible 1500 mm
-
Parallel lever mount:
- Field of view: ± 550 artillery per mill
- Elevation field: 0 to 787 radius per mill
Lever mount
In the case of the lever mount, most of the pipe protrudes from the notch. This has the disadvantage that the pipe is very exposed. The great advantage of this arrangement, however, is that the shutter can be easily reached at any elevation by the loader without special aids.
The lever mount enables the 10.5 cm cannon 35 to be used as a permanently installed fortress gun. The parallel lever guide of the mount relocates the pivot point of the barrel in the reject slot of the gun base. As a result, the opening of the notch can be kept relatively small. The casing is firmly screwed to the floor. The pivot bearing, which is connected to the casing by screws, supports the pivot . This serves on the one hand as a vertical gun axis and on the other hand as a carrier for the parallel lever guide.
Equalizer
The compensator, which is attached to the pivot with two brackets, has two tasks:
- it relieves the weight to be lifted by means of the leveling wheel
- it acts as an impact brake in that the valve-controlled brake fluid in the compensator absorbs the downward shock that occurs when the shot is fired.
Straightening gear
The aiming device is attached to the left of the gun. The side scale is marked on the floor with a vernier. If the directional scale on the ground can no longer be used, you can aim at a mark on the wall behind the gun by attaching the panoramic telescope.
10.5 cm L52 anti-tank cannon on a lever mount
The 10.5 cm anti-tank gun L52 was a fortress gun that was used on the one hand to fight armored targets such as tanks and on the other hand as a "normal" artillery gun.
When used on armored targets, the direct shot was used. The aim was to use a panorama board showing the area. To do this, the firing commander sent the coordinates to the gun with the help of a matrix, or the gun crew aimed at the object independently with the elevation and rudder tubes and took fire at it.
For shooting as a "normal" artillery gun, the reverse target point technique was used. Here the firing elements were calculated by the fire control center and transmitted to the gun via telephone as azimuth (side) and elevation (height).
Main ingredients
- Tube with bottom piece and closure
- Cradle with reverse brake and hauler
- Mount
- Straightening device
- Electric signal system
Technical specifications
- Tube: Caliber 10.5 cm (tube length L52; 52 × 10.5 cm = 5.46 m) Twist: right-hand, constant
- Closure: horizontal wedge closure
- Reverse brake : fluid brake
- Fetcher: Feather fetcher
- Return: constant length, maximum permissible up to 300 mm
- Carriage: Parallel lever carriage for opening minimal notches
Richtfeld
- Directional field 1324 artillery bullet
- Elevation field 909 radius per mill
The straightening device
- Directional telescope
- Elevating telescope
The automatic loading device
The automatic loading device was used to place the floors in each elevation.
Components
- Compressed air system
- Twin compressor group
- Pressure vessel
- Storage boiler
- Compressed air cylinder (as a pressure reserve)
- Main and control switch
- Line system with various pressure reducing valves;
- Loading device
- Loading tube
- Tube parallel cylinder with piston and rod
- Loading lever with control cam
functionality
As a rule, two guns were connected to a compressed air system. There was one pressure tank per gun. The compressed air was used to blow the grenade into the tube. After the shot, the pipe was blown out with the compressed air. This prevented a too high concentration of toxic CO gases from developing in the gun room.
If the compressor system failed, the compressed air was drawn from compressed air cylinders. These were connected to the gun line by means of metal hoses. The compressed air from the bottles was only used to blow out the pipe after the grenades had been fired.
The loading device cannot be used to load the tank shells.
10.5 cm L22 howitzer on a lever mount
The 10.5 cm howitzer L22 on a lever mount is a built-in howitzer model 42 or 46.
Main ingredients
- Tube with bottom piece and closure
- Cradle with reverse brake and pre-hollow
- Carriage with fork carriage
- Straightening device
Technical specifications
-
Tube: caliber 10.5 cm;
- Length (with base) 2310 mm;
- Twist: right-hand constant
- Closure: horizontal wedge closure
- Return brake: hydraulic
- Hollow: hydropneumatic
- Return: variable, maximum permissible up to 1200 mm
- Carriage: Parallel lever carriage for opening minimal notches
Richtfeld
- Directional field 500 artillery bullets
- Elevation field of −80 to +750 radius per mill
Mount
The lever mount corresponds to that of the 10.5 cm L 42 cannon
10.5 cm turret cannon
The 10.5 cm L52 turret cannon is a 10.5 cm cannon 39 of the Swiss Army that is permanently installed in a tank turret .
literature
- Hansjakob Burkhardt: Gotthard Fortress - Fortificazione del San Gottardo Foppa Grande , Koller print and copy, Meggen, 2004 (81 pages online PDF)
- Hansjakob Burkhardt: The Gotthard fortress "San Carlo", the prototype of all artillery works with 10.5 cm tower cannons Mod 1939 L52 , Meggen, 2003 (84 pages online PDF)
- Swiss Army: Regulations 57.210d: "The 10.5 cm fortress guns", fortress artillery booklet B
Individual evidence
- ↑ Regulations 57.210d: "The 10.5 cm fortress guns"