yards away. The range was varied by using a gas regulator to adjust the escaping propellant gases. It was aimed and fired by using a pistol grip at the back that would activate the firing pin when the trigger was pulled. Mk IV = limited production run and did not enter service Mk V = not manufactured Mk VI = not manufactured Mk VII = for use on Universal Carriers Mk VII* = for use by airborne forces, having a shorter barrel ( = 36 cm) and a baseplate replaced with a spade-like plate Mk VII** = infantry use with long barrel and spade-like baseplate Mk VIIA = Indian Army model Mk VIII = another short-barrelled version for the airborne forces Ammunition types High explosive (HE): - olive drab body, red band White phosphorus smoke (WP Smk): - dark green body Titanium tetrachloride smoke (FM Smk): - dark green body Illumination (Ill): - drab khaki (light OD) body Signal multi-star (Sig): 1 lb (white 2 lb) - light stone (grey) body. The multi-star was available in white, red, green, and mixed red-green. Ammunition was packed one 51 mm-bomb per tube, three conjoined tubes per pack (three bombs), two packs (six bombs) to a fibre container, and three fibre containers to a steel box (18 bombs total). Modern variants India's Ordnance Factory Board's 51mm E1 mortar is an enhanced version of the two-inch British mortar of World War II; it is still in production and service in India. Specifications Calibre: 51.25mm (2 in) Weight: 4.88 kg Range: 200-850m Rate of fire: normal: eight rounds per minute high: 12 rounds per minute Bomb weight: High explosive: 950g (800m range) Users United Liberation Front of Assam Naxalites Myanmar Army : Inherited from British-Burma Army and also bought from India.Main Light mortar used until 1990s. People's Liberation Army, Nepal : Free Norwegian forces : Polish Armed Forces in the West The Mk.III (renamed the M3 Mortar) was used by the US Army on the M4 Sherman from Fall, 1943 to Spring, 1945. The vehicle's combat load was 18 smoke shells for M4 tanks with the 75mm or 76mm cannon to 12 shells for M4 assault tanks with the 105mm howitzer. See also Similar, World War 2-era weapons 37mm spade mortar 5 cm Granatwerfer 36 Lance Grenades de 50 mm modèle 37 Type 89 grenade discharger References Bibliography World War II infantry mortars of the