You have probably heard about the American experimental heavy tank T34 somewhere, maybe from World of Tanks, War Thunder or Wikipedia. It’s described as having an excellent penetration at about 247 mm from 100 m, which is a feat compared to the German 8.8 cm KwK 43 gun armed on the Tiger II. But did you know that it could do more than that?

A bit of Background

The T34 was a WWII prototype heavy tank developed in 1945 in response to the German armored threats such as the Tiger II and Jagdtiger. The T29 was considered satisfactory enough in term of performance with its 105 mm T5E1, but lacked serious firepower in contrast to the 12.8 cm cannon. The T30 was only armed with a 155 mm as a bunker buster, with sub-par anti-tank performance across the board. As such, a project was initiated to rearm the T29/T30 with a modified 120 mm M1 AA gun, the 120 mm T53 L/65. Firing a 23 kg heavy projectile at 960 m/s, the gun was able to closely match the performance of said German gun. Unfortunately for the Americans, World War II was already over by the time the T34 was assembled. Post-War development led to the T34’s engine being upgraded from using the Ford GAC to Continental AV1790. Extensive trials of the T34 as a “technology demonstrator” led to the M103 Heavy Gun Tank.

Development

The earliest known record of the requirement to develop the T34 heavy tank was from the first of February, 1945. The Army expressed concern about using the 155 mm gun with heavyweight 100 lb projectiles on the T30 (M112B1), mainly because of the effectiveness of it against enemy tank armor, with the rate of fire calculated in. It was expected to be very ineffective (the M112B1 only penetrates 170 mm of armor from point blank, while the rate of fire from the gun is only 3 RPM). Seeing the potential problem that would likely cause an unnecessary issue in the future, the Ordnance Department went to study for possible application of the 120 mm M1 anti-aircraft gun for the heavy tank.

Continue reading “The 120 mm T53” →

The T30 heavy tank has vague information when it comes to ammunition load. Some claimed it’s only able to fire HE, some said it only has low penetrating AP round, while the others describe it as having high penetrating “M111 AP” and “M112 APCR” that can penetrate 276 mm and 320 mm of armor, respectively.

Some Problems

While some of them are true, there is so little explanation on how the T30 acquired such loadout or achieved such penetration, leading to “what if” situation where the shells are configured according to whatever related sources publicly available.

1. It only fires HE shell

The most common misconception about the T30 is that it only has HE shell. Some people claimed so due to the reason that it’s armed with a massive, but low velocity 155 mm T7 gun used for anti-fortification and destroying building, instead of dedicated anti-tank gun such as the 105 mm T5E1 mounted on the T29. Although it’s understandable since many referenced the source from R.P. Hunnicutt’s book; Firepower – A History of the American Heavy Tank.

2. It fires low penetrating AP round

Information available from certain WWII forum usually points out that the 155 mm “AP” fired from 155 mm T7 was unsatisfactory and only resulted in low anti-tank penetration performance from velocity loss. I will explain this later below.

3. “M111 AP” and “M112 APCR” that can penetrate 276 mm and 320 mm of armor

So far, it’s very popular as these rounds are available in World of Tanks, used by both T30 and T95, even goes so far that the T110E3 and T110E4 received a much improved version with E1 designation in the back that can penetrate 295 and 375 mm of armor.

These projectiles in particular are “M111” AP, and “M112” APCR. It’s interesting and confusing at the same time… The only known use of designation “M111” is a 105 mm APFSDS “Hetz” intended to penetrate the Soviet T-72. While the “M112” is actually an AP round of the 155 mm gun.

… It might be good time to explain this thoroughly.

Opening the Ammo Box

The weapon loadouts will be described as detailed as possible. But let’s start from the basics. The 155 mm T7 L/40 is a 155 mm gun of the T30 heavy tank, developed from a shortened 155 mm M1 L/45 “Long Tom”, conceived as early as 14 September 1944. It was developed alongside with the T29 heavy tank armed with 105 mm T5E1 L/65 gun.

The T30 had up to 5 different ammunition available for use. Starting from M107 HE, M110 WP, M112B1 APBC-HE, T29E1 APCBC-HE, and finally T35E1 APCR. The specification will be listed as fired from the T7.

Continue reading “The T30’s Ammo Box” →