3-inch Mortar

The 3-inch mortar was the standard mortar used by Canadian infantry battalions in the Second World War. The weapons were grouped into a Mortar Platoon, first as part of Headquarters Company and from 1942 as part of Support Company. Six such weapons comprised an infantry battalion commander's personal artillery.

The weapon entered British service in the 1930s, and became widely issued in the Canadian Army in 1940, serving through to the end of the war, and eventually replaced by the US-designed 81mm Mortar.

Historical references cite the calibre of the weapon as 76.2mm. The weapon has been noted for its weight and the long flight times for the ammunition to reach the target due to the high angle trajectory common to all mortars.

Transportation was usually done by Universal Carrier, on which 66 bombs could also be carried, though the 15-cwt truck was also used, which could carry 90 rounds of ammunition as a standard load. The mortar was always dismounted to fire, and the advantage of a mortar was that it could be sited beneath ground level, behind a wall, or in otherwise "dead ground" and thus harder for the enemy to locate.

The mortar could be broken down into a three-man load:

• Mortar No. 1 carrying the baseplate and optical sight (52 lbs)

• Mortar No. 2 carrying the barrel and spare parts bag (51 lbs)

• Mortar No. 3 carrying the bipod and one case of bombs (36 lbs)

3-inch mortar crew of The Regina Rifle Regiment in Normandy, 9 Jun 1944. Their Carrier can be seen in the background. LAC Photo.

Characteristics
 

• Weight: 147.5 lbs

• Muzzle Velocity: 620 fps

• Ammunition Types: HE (High Explosive) and Smoke

• Range

  • (Charge I): 500 yards to 1,500 yds (HE).

  • (Charge II): 950 yards to 2,800 yds (HE).

  • Maximum - 2,800 yds

• Average Flight Time of Bomb (HE):

  • Approximately 20 seconds, Charge I

  • AApproximately 30 seconds, Charge II

• Fragmentation Radius: Up to 100 yards in all directions from point of bomb impact.

• Bomb Weight (HE): 9.99 lbs per bomb

• Elevation: +45º. to +80º

• Traverse: +/-36º

• Crew: generally a minimum of three, not counting ammunition carriers or vehicle drivers

• Weight of weapon in action: 111.99 lbs¹

1. The Illustrated Encyclopedia of 20th Century Weapons and Warfare (Columbia House, New York, NY, 1978) p.2352