My original posting on the Hotchkiss-Puteaux S.A.-L 37 antitank gun was mutilated, so here I am posting it again.
This gun was named 2,5 cm Pak 113(f) in german nomenclature. It was sold, along with ammunition, to the spanish Army by the nazi Germany in 1943, as a part of the “Bär” (Bear) support program for the Spanish army. The Bär program included the Spanish navy and air force too, and was not limited to guns and ammunition, but included radios, raw materials, tooling, etc.
This 25-mm Hotchkiss gun was obsolete by 1943 and it seems that the Germans disposed of them gladly. Probably it was offered by the Germans, not requested by the Spanish Army, that had the opportunity of testing the 37-mm Pak and the 45-mm Russian AT gun during the Spanish Civil War of 1936-1939.
The Hotchkiss-Puteaux 25 mm gun used a rimmed cartridge with a 193-mm long case. The complete round measured 263 mm. The loads were: armour-piercing, armour-piercing high velocity, armour-piercing tracer and armour-piercing tracer high velocity.
The gun used also a 66.6 mm hollow charge grenade that was launched from a muzzle attachment using a special propelling cartridge. This grenade was of conventional hollow charge design and had a ballistic nose cap. The grenade had a rifling in its lower portion, matching the rifling on the muzzle attachment. The grenade weighed 2.000 grams and the payload was 575 grams of TNT. As far as I have seen, the base fuze on this grenade bore no model number (e.g. BZ whatever).