The AMR 33 was lightly armed and armoured; though it was very fast for its day, it proved to be a mechanically unreliable vehicle, especially its suspension elements being too weak.

To counter the threat posed by the massive Soviet arms build-up since 1928, the year Joseph Stalin took power, the French government on 4 July 1930 conceived the plan to form a projection force capable of assisting its allies in the Cordon sanitaire.

[6] On 21 November he was asked by the Section Technique de la Cavalerie to provide a tankette version of his Renault UE to test the feasibility of a tracked AMR-concept.

Being hereby informed of the general outlines of the specifications, he sent on 22 December a representative to supreme commander Maxime Weygand to lobby for a Renault AMR.

[citation needed] That commitment being secured, Renault hastily designed a larger model, a wooden mock-up of which was presented in March 1932.

Based on it an order was made on 20 April of five prototypes for a price of 171,250 FF per vehicle, to be delivered in September before the start of the autumn Champagne manoeuvres.

The experience showed that they were very agile, but also noisy, poorly balanced and lacking sufficient range; unsurprisingly, the crew was always in for a bumpy ride.

[11] After the exercise they were sent back to Renault, who shortly afterwards submitted three types for evaluation to the Commission d'Expériences du Matériel Automobile at Vincennes: prototype 79758, still with the original suspension,[12] 79759 with added internal hydraulic dampers and 79760 with a fully new suspension consisting of a central bogie with a leaf spring and wheels at the front and the back connected to two horizontal helical springs.

On 8 December it was decided to abandon the unrealistic three ton weight limit and install larger fuel tanks and heavier armour, 13 mm thick; the vehicles were again sent back.

It had a wading capacity of sixty centimetres; could cross a trench 1.4 m (4 ft 7 in) wide, or climb a 45 cm (18 in) vertical obstacle or a 50% slope.

This proved to be too awkward and was replaced on the series vehicles by a flatter design from the army Atelier de Vincennes, the AVIS-1, which was moved about a foot to the front to improve visibility.

The 115 vehicles available in 1934 were assigned to the five cavalry divisions, a squadron of fifteen (three platoons of four, two reserve tanks and a command tank) for the GAM (Groupe d'Automitrailleuses) of each, except for 5e DC (which got ten) and 4e DC which, with priority from the first production batch, received forty: a squadron for its 4e GAM and its 18e Dragons and another ten for its 4e BDP (Bataillon de Dragons Portés).

[35] It was originally decided that within each Division's Régiment de Dragons Portés (motorised infantry regiment), both battalions would incorporate two AMR 33 platoons (half a squadron), which, together with six reserve tanks, would create a demand for five times 26 or 130 vehicles, slightly more than the available total of 112.

Around 10:00 on 10 May near Vancé, AMR 33 N° 83950 of 3e DLC had the dubious distinction of being the first French tank to be destroyed in the battle, being hit by German anti-tank gunfire, killing the crew.

In 1934, the three command vehicles of the 4e GAM and 18e Dragons of 4e DC were rebuilt as AMR 33 TSF (Télégraphie Sans Fil or "wireless") by fitting them with an ER29 radio set, the antenna of which was placed on the left rear corner of the hull.

[48] After continuing reports regarding the unreliability of the matériel – often ascribed to the fact that half-trained conscripts were the most frequent users rather than professional drivers – it was decided to investigate whether structural changes had to be made.

The commission concluded on 17 February 1938 that the suspension was fundamentally unsuited for cross-country driving and advised that all existing vehicles be fitted with a new system.

Late in 1932 – this is known by a later confirming letter dated 18 December 1932 – Renault had a meeting with General Weygand, during which he proposed to develop an entire family of light armoured fighting vehicles based on the AMR 33-chassis.

However, on 20 March 1933, Renault received an order from the STMAC (Section Technique des Matériels Automobiles de Combat) to develop a prototype of a different design discussed with Weygand: a command vehicle corresponding to the specifications of 9 January 1931 for a so-called Type M.[51] In September 1933, two prototypes were presented in Mailly, which were rebuilt with a more powerful 22 CV engine in 1934.

[52] On 9 January 1931, the French Artillery officially issued the specifications for a Type P, which was to be a véhicule antichar, a self-propelled antitank-gun, that was to serve in the Maginot Line as a tank destroyer.

The first plans foresaw a very small tracked vehicle, a chenillette, weighing no more than 1.5 metric tonnes, on which a 25 mm antitank-gun was to be mounted on a tripod in an open position.

[53] However, the same year, it was decided to let the 25 mm gun be towed by the Renault UE chenillette, making the Type P redundant in its original scope.

The Artillery therefore decided to mount, under armour, a much more powerful 37 mm Modèle 1934 fortress gun with a muzzle velocity of 860 m/s, which yet had to be developed by the Atelier de Puteaux, the State armament arsenal.

[54] In 1932, Renault delivered a prototype, a specially built chassis (N° 81805), that in general form resembled the standard AMR 33 but lacked a turret and had a raised hull roof.

On 18 April 1935, the CEMAV (Commission d'Expériences du Matériel Automobile de Vincennes), after testing, expressed a very negative opinion: "An ancient and outdated model [...] incapable of rendering serious service".

Moreover, on 24 June, the Conseil Consultatif de l'Armement decided that in future all guns up to a calibre of 47 mm would have to be towed by the Renault UE after modifying the latter type (though this in fact never happened).

The smallest of these, the tracteur de 2 tonnes, which had the factory designation Renault YI, largely used the AMR 33 suspension, though the sprocket was not spoked but consisted of a single convex plate.

[57] AMR 33 prototype N° 78758 was used in 1935 by the engineer Nicolas Straussler, a former citizen of Austria-Hungary who at the time lived in the United Kingdom, to demonstrate his hydraulic "Trench-Jumper" that he already had tested in England.

It proved to be quite effective but in 1938 the Commission de Vincennes rejected the project as the small gain in trench-crossing capacity did not make up for the higher weight.