All these trains were series produced.
First uprising was in 1919, last and most famous was the 3rd Silesian insurrection, which involved the 16 insurgent trains, was 1921 and was for all purposes a full blown invasion of German territory.
How it started? basically Silesia at the time was a area rich in two things: Coal, Industry, and Polish patriots who wanted to unite with the rest of Poland, and the Treaty of Versailles had in fact promised this area TO Poland. Problem was, the Polish got sick of waiting, so they tried to force the issue.
photos of the Polish trains are rare, but the established number was 14-16 trains. they were crude, mostly an armoured locomotive with 2 armoured coal cars with firing slits, no artillery, just mobile pillboxes' for troop protection.
British troops arriving in upper Silesia in 1921 built their own train, of which unfortunately only 1 photo exists, and it shows only the Prussian T 14 locomotive.
however the Germans managed to scrape together enough materiel to create 4 armoured trains to help fight of the Polish attack. These trains were forbidden by treaty.
Because of this event, Germany could with facts on their side, actually say Poland invaded them and this fact was used to great effect to justify the invasion of Poland in 1939, a huge chunk of which was German territory that was lost to the Versailles treaty, with the Silesian industrial region being the most obvious sore spot.
from simply placing a captured T-34 or anti-tank gun on a flatwagon, to mounting broken german tanks in the same way, to the eventual PanzerJeagerWagons using PZ IV Ausf H turrets for this purpose.
as can be seen from the various wagons and guns, this was tossed together with whatever was captured. Sokol included as BP-44 gun and flak wagon along with MG 151 "dreilling" aa guns from a flak wagon.
to see PT16 in epic action in polish service, (ironically playing its original role as German Panzerzug!) see the link here https://www.reddit.com/r/WarTrains/s/xkdDjgxHwz were it plays a staring role in the Polish film Red Rowan. in this fim can also be see the former artillery wagon of Panzerzug 25
only in 1944 was the SP 42 was finally given up on was the flak armed oddity finally made into its own thing and armed with 76.2mm armed turrets from the BP 42 panzerzug. later it had captured T-34 tanks added as Tank Destroyer Cars. PT 16 was the most heavily armoured German railroad unit of the war.
It was part of Battlegroup Steiner in the doomed last stand at Berlin where it was captured intact just a few days before the war ended by the 1st Soviet Polish Army.
After the war, PT 16 and other bits and pieces of surviving former Nazi german armoured trains went on to serve the Polish S.O.K. (Railroad Protection Service) that fought Ukrainian insurgents until 1950.
these were old navy surplus guns given land mobile mounts as an emergency measure to cope with massive and sudden demand for heavy long range land artillery all sides suffered from on the western front.
this is the story of this train according to my pal in Moscow:
"The very first armored train of this series (by which he means the Hunhus-class) did not take part in the Civil War; it was heavily damaged during a battle against Austro-Hungarian forces at Rudochka station. This location is now known as Tsuman, in the Lutsk Raion of Ukraine's Volyn Oblast. It fought its only battle on September 24, 1915. Afterward, it remained in no-man's-land until the end of 1916. Following an offensive in early 1916, the region was captured by Russian Imperial troops, but a technical commission that arrived on the scene determined that the armored train was beyond repair.
It appears that its rear armored car was successfully evacuated. However, the subsequent fate of this armoured car is unknown" (likely scrapped or donated to another train)
along with armoured trains, the small warships of the Ost Front at another generally unknown element of ww2 in the west.
Armoured Train No.5 Железняков or "Zheleznyakov" of the Black Sea Fleet, named after an anarchist sailor turned Bolshevik armoured train captain of the civil war era, was a veritable land pirate ship tossed together in 15 days in Sevastopol's shops.
She fought for 6 months during the apocalyptic Siege of Sevastopol, using the many tunnels for cover against attack and night to obscure it's movements in much the same way as "Anzio Annie" did in Italy.
it was armed with multiple 76.2mm guns, three 34K naval guns from a sunken ship and 2 of the old reliable 1910 model lender guns much used on armored trains. it had a large number of DsHK model 1938s for air defense and it also had 120mm mortars on one of its wagons.
It shot down at least 3 German aircraft, which given the terrain and heavy AA armament we see in this clip, is not surprising over a 6 month period. Its role was much more the simple artillery support unlike the German guns in Italy, it was able to move troops around as well and provide a mobile reserve, which made it much more versatile then a simple artillery battery.
Imagine if Quarritch was commanding this thing, instead of the Sea Dragon? that would have been WAY COOLER.
Screenshots taken from space marine II's "Ballistic Train" Mission where you must load a MASSIVE nova cannon warhead on the train and send it to blow up a hive city full of nids.
This panzerzug was made from the captured parts of three Soviet armoured trains used in the Battle of Crimea and Siege of Sevastopol.