Two things first,
- This isn’t supposed to be a suggestion because the weapon system is mounted on a trailer, which from what i’ve found makes it not eligible to be in Gaijin’s pool of vehicles that they want to add to warthunder.
- The difference between an autocannon and a cannon with an autoloader is that you can fire multiple with one trigger pull while a cannon with an autoloader you have to pull the trigger for every shot.
Background:
In the early 50s Swedish army wanted to replace their older mid & large caliber anti aircraft guns, simply because they lacked in firerate & range. Bofors AB was tasked with said project. Bofors had a couple years earlier made a dual 120mm turret for the Halland class destroyer. They decided to take away one of the two guns to simply save weight, but that would reduce its fire rate, so Bofors decided to increase its fire rate from 40 rpm to 80 rpm, but with such high fire rate it would quickly overheat the gun. To solve this problem they fitted the gun with a water cooled jacket, the water would be going through the jacket by a pump from a 500L tank. The magazine where split in two, both parts had 4 racks with 5 rounds each, under each part there where a tray that had an extra 6 rounds, making the total capacity 52. The turret could rotate 360°, with a horizontal traverse rate of 32°/s, and a vertical traverse rate of 25°/s, which is at the level of a Leopard 2. The elevation was between -5° - +85°
To show its its +85° elevation
The gun fired the same shells as the SAV 20.12.48 fires, but with the addition of a HE-VT version of the SAV’s HE shell. Putting in the information about the APCBC shell and its increased velocity in the penetration calculator you get 172-184mm at 0m & 0° depending on what velocity the shell gets, (800-835m/s).
There were plans that it would in the future fire APDS, but it was abandoned in 1954 because it would increase the development time of the gun. Sadly only one prototype was made but the naval variant serves the Finnish and Indonesian navy even today.
Shell info pics ( in Swedish):
Video of it shooting:
Extra pictures:
Specifications:
Spoiler
General:
- Crew: unknown, but probably 3
- Driver
- Gunner
- Commander
- Weight: 23t (gun+trailer+truck)
- Protection: 4mm (material is unknown)
Since it’s a trailer it doesn’t have any form of propulsion, but if we take the truck its getting towed by in most of the pictures or videos of it, it is a version of the Ltgb 957 without the cargo bed.
And if we use its stats we get:
- Top speed: unknown, but probably ~44 - 60km/h
- Reverse speed: unknown,but probably ~6 - 10km/h
- Engine: Scania-Vabis DS10R02 10L In-line 6:
- 220 hk
- 814 Nm
- Transmission: GT 84:
- Manual
- 10 forward gears
- 2 reverse gear
Armament:
-
Bofors 120 mm Automatic Gun L/46:
-
Barrel data:
- Length: 5520 mm
- Caliber length: L/46
- Chamber pressure: 2650 kg/cm^2
- Weight of barrel with breach: 2300 kg
-
Turret data:
- Firerate: 80rpm
- First stage ammunition / in autoloader: 52 rounds
- Elevation: -5° - +85°
- Traverse: 360°
- Horizontal traverse rate: 32°/s
- Vertical traverse rate: 25°/s
- Horizontal traverse acceleration: 64 °/s2
- Vertical traverse acceleration: 50 °s2
- Moment of inertia system: 28000 kgm2
- Recoil resistance with muzzle break: circa 16000 kg
- Recoil length min - max: 420 - 495mm
-
-
Ammunition:
- HE:
- Weight: 23.5kg
- Explosivemass: 2.3kg
- Explosive type: TNT
- Velocity: 800-835m/s
- HE-VT:
- Weight: 23.5kg
- Explosivemass: 2.3kg
- Explosive type: TNT
- Velocity: 800-835m/s
- Fuze type: proximity fuze
- APCBC:
- Weight: 23.5kg
- Explosivemass: 890g
- Explosive type: TNT
- Velocity: 800-835m/s
- HE:
Sources:
Spoiler
The worlds largest autocannon – From the swedish archives
Delivery specification for 12 cm automatic field-gun (F - Album on Imgur
Firing table 12 cm akan m/50 - Album on Imgur
https://www.youtube.com/watch?v=1wnae3wClAk&list=PPSV&t=407s
Lastterrängbil 957 – Wikipedia
BroTgb 9572 - Smålands Militärhistoriska Sällskap • SMHS
Bofors 120 mm Automatic Gun L/46 - Wikipedia (not really used)
If ive missed some memo and this would qualify as to become a suggestion Ill be happy to make it one.
