In April 1944, the Australian Army conducted series of tests on the Matilda tanks they were using against Japanese forces. These tests featured a variety of shells - Armour Piercing, High Explosive and HEAT rounds fired from a ‘Meiji’ Type 41 75mm Field Gun.
The tests were carried out by the Operation Research Section of the Army Ordnance Corps at the HQ of the 5th Division at Fortification Point, Papua New Guinea on the 4th to the 6th of April 1944, using both static shell testing, where the shell is held at a fixed point and detonated and using direct fire from the gun itself. The captured gun in question was fired by men from the 2/14th Field Regiment and serviced by the 2/83rd Light Aid Detachment.
Firing was conducted at a range of 150 yards (137metres) and a multitude of rounds were fired with mixed results. The Type 41 Field gun is 17.3 calibres field gun, very light and handy, weighing very modest 540kg and is able to put out a 5.71kg 75mm shell at 360m/s. So, the testing method may look a little crude using a forked stick but this is ideal as it holds the HE shell in place for the test.
Another static shell test, this time of a Hollow Charge shell placed against the frontal armour. Being a static test, it will actually improve performance as there will be no loss of penetrating due to the rotation of the round, but the purpose is clearly to ensure that the shell is detonated precisely where they wish to test the impact.
Hollow Charge round hitting Matilda on the glacis plate directly in line with the drivers view port. Despite making a significant indentation into the plate, the round is not recorded as penetrating.
Impact from 3 hollow charge rounds against the front armour. No recording of any penetration of the armour.
Hollow Charge shell number 12 fired from 150 yards hitting the front armour of the Matilda. Round did not penetrate.
Armour Piercing shell hitting the front armour of the Matilda. Round did not penetrate.
Three separate Armour Piercing rounds this time hitting the area around the drivers view port shearing it off. Two hits in the corner where the port meets the vertical part of the hull and don’t penetrate. Round three is less clear as it has sheared off the edge and shoulder of the vision periscope. Would have to put this one down as a non-penetrating hit too. To the left of the view port as you look at the image you can see another, earlier hit described below.
This is the Hollow charge round strike before those AP rounds sheared off the drivers view port seen from the outside.
Inside view of the penetration (that tiny hole above the white rectangle) through the front by a fired Hollow Charge round, the exterior of this section can be seen in the above image.
This is a cut section from the front armour of a different Matilda with the vision slit on the left. In this case a Hollow charge round has struck at a descending angle the edge of the periscope mounting where the front armour is much thinner and penetrated. Now, the armour is only much thinner there because the big circular piece of steel holding the periscope in place behind has been removed. It's not actually a weakspot in the armour. Of note is the splash across the rest of the armour as a result of the explosion.
This is the inside view of that hit and to test the behind armour effect a sheet of sisalkraft paper was placed 20 inches (50.8cm) behind the target.
So what can we tell from these trials? Well, for starters, the Matilda was still a capable tank even in 1944 and also that the Type 41 Field Gun firing Hollow Charge shells was a potent anti-tank weapon. The AP rounds all failed to penetrate and the results of the HE shells aren’t even shown presumably because they were so ineffective. All of the efforts focused on these Hollow Charge rounds showed them to be inconsistent at best.
Australian War Museum Archive