Firing Mortars in the Jungle
A technique for avoiding overhead tree branches
Early in 1944, the commanding officer of the Third Marine Regiment submitted a 45-page report on ‘tactics and technique’ that, among many other things, described a method for firing infantry mortars in places well supplied with trees.
Use of Mortars in the Jungle
The jungle presents no obstacles to the use of the 60mm and 81mm mortars that cannot be successfully and quickly overcome. Mortar leaders, from squad to platoon, must, of course, exhibit unusual initiative, ingenuity, and skill, and mortar crews trained to the peak of perfection.
Equipment and demolitions for topping trees or otherwise clearing fields of fire must be available to the mortar squads, but the best mortarmen will, by vigorous reconnaissance, frequently locate clearings from which one or more mortars will be fired, particularly if the highest rather than the lowest number of increments is used, in far less time than would be required for the clearing of a field of fire.
Not infrequently, when mortar fires were urgently required, a test for mask clearance was made by firing a shell from which the safety pin had not been removed. If the shell went clear, the concentration was delivered without more ado.
Note:
The term ‘increments’ refers to the modular propellant charges used with American infantry mortars of the Second World War.
Sources:
US War Department TM 9-1904 Ammunition Inspection Guide (1944 ) page 287
3rd Marine Division Operations in the Bougainville Campaign (1 November - 28 December 1943) Enclosure F (Report of the 3rd Marines) page 19 (To read a document without downloading, click the bright blue ‘expansion button’ in the upper right hand corner of the image.)
The 4.2 inch mortars attached to my Maryland ARNG battalion (115th) had a recurring problem with the old ammunition they were using in the early and mid-1970s, rounds often left the tube and just dropped onto the ground as the mortar crew scattered as fast as they could.
We learned about short 60mm rounds one day at the K-Ranges at Camp LeJeune. In training the 0341 basic mortar men one day it was raining then raining hard. We had four (full) increments and had a target out about 800 meters (old amtrac hull) the rain got heavy and all manner of things went wierd. Like nothing was even close to the target which we knew like the back of our hands and ought to have dead on. As RSO and Chief of Weapons Instruction we suspended firing, before a couple of rounds were in the near vicinity of “danger close” we wore helmets and flak jackets for a reason, most of the time it seemed overkill….not that day!!