one of the vehicles Yuri Pasholok saw and photographed in Thun is the 4.7 cm Pak (t) (Sfl.) auf Fgst.Pz.Kpfw.35 R 731 (f) - German conversion of the Renault R35 light tank by monting a boxy superstructure and the Czechoslovak 47mm gun, creating an improvised tank destroyer.
As a result of the fall of France, between May and June 1940 the Germans captured some 850 Renault R35 light tanks, of which roughly 800 were pressed into German service one way or another. Most of these vehicles were equipped with the old 37mm SA18 guns and were good only for infantry support. About a hundred or so were indeed used in their original form - either for training or for police duties.
Combat-wise, the obsolete French tanks were mostly useless but there was a way to make them "useful" again - by converting them for various other roles, especially the one of self-propelled artillery. On 23.12.1940, the company Alkett received a task to create 200 self-propelled guns based on this light tank. A prototype was ready on 8.2.1941 and was approved shortly after for service and the contract was thus confirmed - of the 200 ordered vehicles, 174 were supposed to be tank destroyers (such as the one this post is about) and the rest were to be commander vehicles. First 93 vehicles were built in May 1941, 33 in June, 5 in July, 22 in August, 28 in September and the rest in October.
The first vehicles of this type went to the units located in France but the first combat experience came soon enough with Barbarossa. 93 vehicles (81 TD's and 12 commander vehicles) were transferred to the 559., 561. and 611. Pz.Jg.Abt (Sfl) fighting on the eastern front in summer of 1941, in particular they were used during the fighting in Belarus. They were however used only for a few weeks, after which they were only used by the occupying forces in France and on the Jersey and Guernsey islands. On 1st of April 1942, 147 vehicles were still in active service and in the early 1944, 110 were still active. They were actively used against the Allies in Normandy but some survived and were used even later, for example during the Arnhem fighting. The vehicle located in Thun is most likely one of the Normandy ones.
The hull was not different from the original R35 tank - it was not heavily modified. The tank destroyer was only about a ton heavier than the light tank itself and thus no modifications to the hull were needed. The Thun vehicle was clearly in combat, it is damaged and some parts are missing. The main armament was the 47mm Czechoslovak gun A6/A9 (PaK 36 (t) in German service), until the appearance of the 50mm PaK 38 it was the most powerful German-used early war AT gun. Interestingly enough, the Germans tried also to mount a 50mm gun on such vehicle but it never did go anywhere.