I would like to suggest the IFA W50 Truck with the 2,5 cm 2M-3 twin naval AA gun on the flatbed.
It was build in East Germany in the mid 60s.
The history about the conversion is very little known, the 2M-3 Gunmount was taken from Stock, decommissioned boat or a scrapyard and build to strenghten the mobile AA force as there werent enove ZSU 57-2. Possibly mainly for use as mobile object protection (at least by a photo title).
The Truck came into production in 1965. The IFA W50 is a medium duty truck by the East German company IFA in Ludwigsfeld, with a total of about 572.000 build there with production ending on 17.12.1990 after the reunification of Germany.
Mass 4.6 tons for the truck
1.5 tons for the turret
Length 6.53 m
Width 2.50 m
Height 2.60 m (without turret)
Crew 4 (Driver and commander in the cab. gunner and loader in the rear)
Armour 10mm on all turret side
Assumly 10mm on the turret mount
armament 2x 25mm 110-PM L/79 auto-cannon (gaz operated)
Engine 4-cylinder 4 KVD 14,5/12 SRW
Diesel water colled
110 PS (81 kW) at 2200/min
Power/weight 18.3 hp/ton
Wheelbase 3200 mm
Ground clearance 300 mm
Fuel capacity 100 l
Speed 83 km/h, truck empty
The Gun, 2M-3 Mount with 2x 25mm 110-PM guns.
It entered service in 1953 armed with 2x 25 mm 110-PM L/79 guns. They existed in 2 generations, with long recoil and a fire rate of 450 rpm each and gas operated with 600 rpm each. The 2M-3 uses the gas operated version and will come with a combined fire rate of 1200 rpm, as long as there is ammo.
The ability to load from 7 round clips was available, however standart ammo loading was from boxes with 65 round belts, so 130 rounds at a time, with an unknow amount of reserve stored behind cabin.
It has 360° traverse with -10° to 85° elevation, with a speed of 40°/sec (traverse) and 70°/sec (elevation)
Ap-T 0,28kg 900m/s 55mm/10m
Fi-T 0,28kg 900m/s 20g A-IX-2 (30,8g)
It would add an fun and mobile 25mm AA gun, at the medium to high ranks (around 5.0 or so). Germany doesnt yet have a full truck AA nor an AA from East Germany. It will be rather unique in having a high fire rate with relativly good power against light ground targets as well as planes, while also beeing rather vurnable as only the turret has armor.
The gun can allready be found on russian ships.
Plaste Blech und Planwirtschaft — Die Geschichte des Automobilbaus in der DDR
The Naval Institute Guide to World Naval Weapon Systems 1991/92
Jane’s Ammunition Handbook: Ninth Edition 2000-2001
Jane’s Fighting Ships 1998-99