[Hanno Spoelstra]

From Equipment Used By The Infantry Regiments:

As the war progressed it was realised that at heavier mortar was needed to provide more support, especially for the infantry units and so the 4.2-in Mortar (pictured left) was developed, based upon the Chemical Weapons Design from the Great War. The British version differed from the US one as the latter had a rifled barrel. The 4.2-in Mortar was a simple and rugged design and used a wheeled base plate for easier movement.

It was first used in North Africa, by the Chemical Warfare Companies of the Royal Engineers at El Alamein using conventional ammunition. However, from about mid-1943 the Divisional Machine Gun Battalions (one per Infantry Division) and Independent Machine Gun Companies (one per Armoured Division) were converted to included one Mortar company or Platoon respectively operating 4.2-in mortars. For an armoured division's Independent MG Company an extra platoon was added with 4 mortars.

4.2" Mortar, Data:
Calibre (in/mm): 4.2/107
Ammunition: HE/Smoke
Weight (Unloaded) (kg/lb.): 599/1320.6
Length (mm/in): -
Rate of fire: -
Bomb Weight (kg/lb.): 9.08/20.02
Effective Range (m/yards): 3750/4100


http://www.surfacezero.com/g503/data/836/4_2Mortar.jpg