Brass cased 20mm calibre cannon round for anti-material purposes. Most common variant was the HEF-I (High Explosive Fragmentation Incendiary). Present on most belts available on British aircraft. It is a conventional HEF shell with approximately 13 grams of explosive and incendiary fillers. It is also quite heavy and (as with all hispano rounds) is fired at a very high velocity of 850 m/s, which in theory makes it quite an effective kinetic round. In practice, this is not the case, as this shell has an impact fuze with no delay and thus usually explodes the moment it hits the enemy aircraft, punching a small hole and spraying a few fragments. Also made as Ball, Armour Piercing and Tracer.
