- Yes
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A.K.A.: Volvo Roundnose w/ Bofors 20 mm m/40
Shortened Swedish: 20mm Lvakanplint till Tgb m/42
Simplified English name: 20mm AA-mount for trucks (Volvo Roundnose),
or, Universal 20mm AA-mount for trucks.
Since this is a mounting system meant for a variety of trucks, it’s hard to give it a specific name. But, since the manual uses a Volvo Roundnose truck, I’ve concentrated this suggestion on that model.
Photo: User Manual - Beskrivning av lvakanplint till lastbil.
Gameplay
This is an entirely unarmored vehicle and so a cautious play is needed during travel. But once in place, the unusually tall height of the gun means that you can easily peak over rolling terrain features, rocks and small obstacles and get shots off without exposing the rest of the vehicle. The height would be quite unusual and be a fun quirk to play around with. The novelty it brings being typical of many Swedish tech tree vehicles.
Being a low-tier vehicle, enemy HE-rounds aren’t common, which means when fired at it would only be the exposed gunner that would be hit, and he will often be shot with kinetic rounds without damaging the rest of the crew, after which the lost crew member could safely be replaced without losing the entire vehicle, giving a sort of increased survivability for the whole vehicle.
Description
Spoiler
The Lvakanplint (“Luftvärnsautomatkanonplint/Anti-Air Autocannon Plinth”) is simply a steel frame stand for carrying the Bofors m/40 20mm AA autocannon, that can be easily installed on almost any truck without taking up load-space in the truck’s cargo bed, and provide clear 360 degree traverse and view for the gun.
The stand was simply attached and tightened down with nuts and bolts that went through the frame and pre-drilled holes through the timber planks of the truck’s bed (I haven’t found any information if trucks with a metal cargo bed floor were meant to carry this, or if there were any that were in use at the time). After the stand was in place the entire Bofors m/40 20mm gun system was placed on top of it and locked in place.
This simple solution could quickly turn any truck with a wooden cargo bed into a mobile AA-platform, without needing a dedicated military AA-vehicle for protection and escort duties and without necessarily sacrificing cargo space. In order to not take up too much of this cargo space, the stand is built in a square U-shape that conforms to the cargo bed’s sides and the rear of the driver’s cab, with an unobstructed opening in which cargo can be slid in and out of, with about one meter in height in clearance from the cargo bed floor.
The height of the frame helps the gun and its mount to sit above the driver’s cab roof which allows for a full and unimpeded traverse and gun handling by the gun’s operator while he is in postition. The mount also has two spare drums for the gun placed on it. For further ammunition needs, nothing is instructed, but a fair guess would be one or several ammunition boxes could be carried on the truck, which would not be difficult considering the trucks this system is meant for are cargo trucks to begin with.
Unrelated, game-wise, is the the frame-stand comes with its own little crane system that can lift the gun up after the frame-stand has been securely bolted into place. The crane can be up to 3 meters tall (presumably that includes the truck) and carry a max weight of 500 kilograms and is operated using a normal chain hoist. This crane system was, like the rest of the construction, utterly simple and reliable to install and use by pretty much anyone.
Armament
Spoiler
Category Details Name 20 mm automatkanon m/40 (20 mm akan m/40) Caliber 20mm (20×145mmR) Elevation -5/+85 degrees Traverse 360 degrees Weight (with equipment) 313 kg - Weight (truck system) ~320 kg Cyclic Rate 360 rounds-per-minute (360 rpm) Magazine Capacity 25 round drum Magazine Weight (loaded) 12 kg (4 kg empty) Muzzle Velocity 810 / 815 / 845 m/s Ammunition Load x3 25-rd drums, plus ammobox wherever on the cargo bed. Ammunition Types HE-T, HEI, HEI-T, AP-T Optics Iron sights (x1.0) Ammunition
Spoiler
Name Type Muzzle Velocity Mass Filler Filler Weight Slsgr m/40 HE-T 815 m/s 145 grams TNT 5.5 grams Slsgr m/41 HE-T 815 m/s 139 grams PETN 8.0 grams (13.6g TNTe) Slsgr m/42 HE-T 815 m/s 136 grams PETN 6.0 grams (10.2g TNTe) Brandsgr m/42C HE-I 845 m/s 133 grams TNT + Phosphorous 6.0 + 2.0 grams Slbrandsgr m/51 HEI-T 815 m/s 145 grams Incendiary mix #8 13.4 grams Slbrandsgr m/51B HEI-T 810 m/s 145 grams PETN + Incendiary mix #8 + RDX (detonator) 2.6 + 10.8 + 0.6 grams (5.38 TNTe) Slbrandsgr m/511 HEI-T 810 m/s 145 grams PETN + Incendiary mix #8 2.6 + 10.8 grams (4.42g TNTe) Slpprj m/40 AP-T 815 m/s 145 grams N/A N/A Slpprj m/42 AP-T 845 m/s 136 grams N/A N/A Incendiary mix #8 contains about 2.6 grams of PETN with the rest (10.8 grams) being a mix of aluminium powder, barium nitrate and binder. All shells with the #8 mixture listed here contains a total of 13.4 grams of this mix. The m/51B also has a detonator with 0.6 grams of RDX.
Source: V 650 Ammunitionsregister för armén, Data och bilder, Kungl armétygförvaltningen (1972).
Vehicle(s)
Spoiler
As stated, this was meant to be installed on a wide variety of trucks, so it’s up to the devs to decide what would be the most fitting. But the official manual for this system does show a specific truck in its images, which is a military or militarized variant of the Volvo “Roundnose” trucks.
A military pattern Volvo Roundnose at F15 (Hälsinge flygflottilj), Söderhamn. Note the protectors around the head lights, the front bumper and the simplified tire mudguards.
Source: En värnpliktig bilförare vid en "Volvo Starke", F15 Söderhamn. -Digital Bild i Söderhamn / DigitaltMuseum
A Volvo Roundnose that has been dressed up to look the part. This one has the classic “rounded” civilian mudguards and no protection around the headlights, but retains the front bumper. Another note is that it’s one of the tall Roundnose variants, as identified by the extra plate added below the side vents of the engine compartment. In the Lvakanplint manual, that is missing from its truck. The pictured one here is likely one of the trucks specialized for use in off-road terrain, with the engine sitting higher off the ground. A helpful note for anyone trying to distinguish or model these.
Source: Arsenalen’s facebook page.
Exact Roundnose model?
Determining the exact model of the Roundnose is difficult. There were many models of the Volvo “Roundnose” that were used by the Swedish military. The most common variants were in the LV 120-, 130- and the 140-series (LV meaning “Lastbil, Volvo” / “Truck, Volvo”).
Either way, the variants don’t differ much gameplay-wise except for the engine power and weight, which were as follows:
Series + tonnage Engine Name Horsepower at revolutions LV-120, 6.5t FC 6-cyl 90 hp 3,000 RPM LV-130, 8.0 - 8.25t FC/FCT 6-cyl 90 hp 3,000 RPM LV-130, 8.0 - 8.25t FET 6-cyl 105 hp 2,500 RPM LV-120, 8.3 - 8.5t FET 6-cyl 105 hp 2,500 RPM Both engines could be driven on either gasoline or motyl (mix of gasoline and alcohol).
Both also used a 4-speed gearbox. Starting with the LV 131, 4x4 drive was implemented (previously 4x2 RWD) and a 2-speed transfer box was installed. Gameplay wise, I believe this would double the amount of gears available, leading to better acceleration.Total weight is used above. Service weight is only a bit more than half (~55-65%), depending on variant (4-5t).
Note: There are many vehicles (Tgb) with the m/42 designation with different suffixes. In this article I’ve decided to simply use “m/42” since the exact model isn’t known, nor that important due to the flexibility of installation of the system on different trucks.
For an idea of the many designations for the Roundnose alone, below is a table of the most common Roundnose trucks adopted (plus data).Spoiler
Source: Volvo i Uniform, Jean Christer Olsson, page 35.
Looking at a few photos from the Danish site armyvehicles.dk, we can see a photo each of both the Volvo TLV 141- and 142-series with the typical military modifications (clearly on at least one of the pages), used by Swedish-trained Danish “Police Forces” that were used at the end of WW2 in both Norway and Denmark. It could be very well one of these type of variants that we see in the manual.
The two most common modifications for the military vehicles were simplified mudguards for the wheels and steel protectors around the front lights. As noted earlier, some also received 4x4-wheel drive (4WD) with a reduction gearbox for traveling in rough terrain. Another neat modification that could be done, at least on the Tgb m/42 model, was that you could attach an extra two front wheels for better terrain crossing (one next to each front wheel on the outer sides).
A tanker truck model with the headlight protectors, front bumper and simplified mudguards. The text notes: “The tanker trucks delivered 1946-1947 can be recognized by their flat mudguards and front bumper. This image from 2. division at F9 is unique in that it has the division emblem “Bonzo” painted in a blue circle on the door.” Source.Recognize that emblem on the door? We recently got it in the game. And wouldn’t it be great to have a fitting truck in the game to go along with it? It would create a nice little connection at the very least. :)
Emblem ("Ivar Blå")
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General Specifications (unified system)
Spoiler
Category Details Crew 2-3+ (driver, commander, gunner, loaders) Weight 4–5 t (model dependent), plus 320 kg for weapon system. Armor None Engine (TLV-120/130) 4.39L FC/FCT 6-cyl, 90 HP @ 3,000 RPM Engine (TLV-130/140) 5.65L FET 6-cyl, 105 HP @ 2,500 RPM, Transmission 4-speed manual. Armament 20 mm m/40 Bofors autocannon Rate of Fire 360 rounds/min Muzzle Velocity 810 / 815 / 845 m/s Ammunition Load x3 25-rd drums, plus ammobox wherever on the cargo bed. Ammunition Types HE-T, HEI, HEI-T, AP-T Gun Elevation −5° to +85° Optics Iron sights (x1.0)
Final Thoughts
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Why this system is so obscure and seemingly unused and fairly undocumented is not exactly known by me. My own theory would be that it was pretty obsolete by its introduction, as aircraft became faster and faster, especially with the new jet aircraft at this time, and that the gun lacked potency and range against these aircraft. Gleaming from a post by Arsenalen, it seems that tests were done on a variety of vehicles. The post there showing and image of an early improvised construction sitting on a GMC CCKW 6x6 2 1/2 t truck, according to one comment. The Lvkakanplint I have suggested here may be the end result of those tests, being quite simplified and lighter than the rather large and clunky construction we see in that picture.
Pic below:
Maybe someone of you will suggest this earlier one? :>
Thank you for reading!
Also, shout out to Thomas_Belgium for his permission and help in formatting this post!
Sources
Spoiler
Note to moderators: If needed, I can provide images of all the physical sources. I didn’t want to spam all the images here and there’s usually an image limit I didn’t want to surpass. Just shoot me a DM and I’ll get it for you. :)
Mount System
− V 243. Beskrivning av Lvakanplint Till Lastbil. Fastställd av Kungl arméförvaltningens tygavdelning. År 1952. First-hand source, physical literature.Armament
− Vapenregister för armén. 1951 års upplaga. Faksimil, Svenskt Militärhistoriskt Bilbioteks Förlag 2019. ISBN: 978-91-88885-04-3. (physical literature)
−− Ammunition:
− Ammunitionsregister för armén 1949, del 1. Literature (online link [https://tanks.mod16.org/pdf/Amregister%20I,%201949.pdf ], .pdf pp. 33-34).
− Ammunitionsregister för armén 1960. Literature (online link [https://tanks.mod16.org/pdf/Amregister,%201960.pdf ], .pdf pp. 31-32).
− Ammunitionsregister för armén 1972, V 650. (physical book).Vehicle
− Volvo TLV 141 - Danish Army Vehicles Homepage - Danish LV 141
− Volvo TLV 142 - Danish Army Vehicles Homepage - Danish LV 142
− 1940-talet | Volvo Lastvagnar - General info from Volvo of the Roundnose models.
− Volvo LV120 – Wikipedia - Some helpful information of a few models and data.
− Volvo Roundnose - Wikipedia - Tgb m/42 and some variants, if the community and/or devs want to use that one instead.
−− Volvo Roundnose - Wikipedia - English page of above.
− En värnpliktig bilförare vid en "Volvo Starke", F15 Söderhamn. -Digital Bild i Söderhamn / DigitaltMuseum - Normal Roundnose very similar to what we see in the manual.