I would like to suggest this WW1 Truck AA gun, the 3,7 cm Sockel Flak L/14,5 mounted on the reliable and prooven KD-I Artillery tractor. Along the other mounted guns on KD-I and Benz Gaggenau (mostly 7,7 cm, 7,5 cm and 8,8 cm guns) were also a 3,7 cm Sockel Flak L/14,5 mounted.
What is the 3,7 cm Sockel Flak L/14,5?
Its an early development of an full auto 10 round magazin fed 37mm Light weight gun originally envisioned to be mounted on Zeppelins as Air defence as well as to shoot at ground targets, as well as in bombers.
And Zeppelins had (along others) a flaw, weight. Duo to the main planned use the gun had to be small (only a L/14,5 barrle) and light (full combat weight with the Sockel (the Mounting) of just 215 kg. For comparisson the 3,7 cm Flak 37 L/57 is full weight 1,550 kg and the 40 mm Bofors L/60 is 1,981 kg, so this small 37mm gun is extremly light for its class.
But along the less usefull use on Zeppelins and their use on bombers, the idea to use them as ground based AT (less usefull as well) and AA gun both stationary and mobile along the german use of the 37mm Hotchkiss revolver cannon and the Flak M14 Pom-Pom (they all used the same round (not casing)).
And such i am suggesting here, there exist a singular picture of the KD-I mit 3,7 cm Sockel-Flak L/14,5, it was build and used by the german Army near the end of WW1 and then went into use with the Nether as reperations.
Pictures: (Click to show)
In Game it could be a 1.0 sidegrate (or well worse AA than Flakpanzer I) and would be another WW1 addition that would be fun, (somewhat) usefull in its main role, however will rather lack in the AT role, duo the velocity. Against Biplanes and WW1 tanks as well as Halftracks and Trucks it will be rather good, but beyond that a mere fun WW1 vehicle.
Overall the usefullness is somewhat doubtfull because of the low velocity of just 355-360m/s against ww2 tanks. But it will be usable and fun against biplanes, as the He grenades dont actually have a tracer, but lots of filler. The SapI-T ammo with all of 14mm penetration will only be able to destroy light targets as well as (if there will be more WW1 tanks some day) the British Mark tanks through their 12mm side armor.
So while it looks bad on paper, i still think it deserves its place in game and will be fun to use as it certainly can be used. As while not the best, there are certain advantages, such as Tracerless He ammo (you may be able to detrack someone and flee befor they find you) and ultra light recoil, as its just so weak compared to other guns mounted on a fairly massive vehicle with a solid heavy duty pintle mount (relatively to the field mount which is quite light.)
Furthermore it will hold the record of the shortest barrle as with L/14,5 it is shorter than the current record holder, the 3,7 cm SA 18 L/21.
3,7 cm Sockel-Flak L/14,5
Weight: 215kg 120 RPM 355 m/s for the o,47 kg He and 360 m/s for the 0,465 kg SapI-T velocity. -5° to + 80° elevation. Ammo Storage unknow, the normal storage wooden boxes were placed at the back of the flatbed, around 400 rounds (40 Mags) or more seems realistic.
Overall 4 rounds existed, however game play wise only 2 are of importance. 2x He rounds and 2x SapI-T rounds existed.
these include the: (Click on the name to show.)
Sprgr. L/2,5 (Kz.)
Here a link to replica L'Spur.-Gr. L/2,5 (Stahl) (Click to show)
The Gr. L/2,5 is just a basic He round filled with Black Powder and only Cast iron, the Sprgr. L/2,5 (Kz.) was a dedicated AA He grenade which has an improved filler of TNT and Pirecic acid with an TnT aquivalent of 42g (while still a filler of 22g, on the blueprint is is written as filler 0,022 kg and brutto (gross) 0,042 kg) and is made of steel.
Then there are the SapI-T rounds made of cast iron and one of Steel with an increased tracer filler.
However in game only the Sprgr L/2,5 (Kz.) and L’Spur.-Gr. L/2,5 (Stahl) will be usefull.
Because the He grenade will have 42g TnT aquivalent and the SapI-T will have 14mm penetration, while the other standart He is less powerfull and Cast Iron instead of Steel as well as the (Stahl) grenade is also steel instead of Cast iron.
In game 3 Belts should be made for the gun, because of the ammo available, as the He grenade has no tracer, the default belt should be 50/50 mix and then 2 pure belts.
Vehicle: Artillerie-Kraftzugmaschine Krupp-Daimler 100 PS
Weight: 8000 kg
Length: 6265 mm
Width: 2170 mm
Height: 2860 mm
Axle articulation: 30°
Engine: 4 or 6 cylinder 100 HP/74kw engine
Speed: 8 gears forward with 65 kmph (conflicting sources, going from 36 kmph with 10t attached load to 65 kmph)
3 reverse gears to 8,5 kmph
Ground clearance: 400mm
Turning radius: 6,5m
Crew: for this vehicle in game somewhere between 6-10
Armor: around the Hull 3-4mm (wow so thick, will deflect some small he rounds and rifle bullets from afar, nothing more)
Das Gerät der Artillerie vor, in und nach dem Weltkrieg
Encyclopaedia of the German Army in the 20th Century
Vom Einzelschuss zur Feuerwalze: der Wettlauf zwischen Technik und Taktik im Ersten Weltkrieg