The Art Of Tank Warfare - Chris Keeling

meters that it could at 10 meters. A shaped charge round mounted on the end of a stick and muzzle-loaded
into the 37mm antitank gun was even developed by the Germans! Other types of ammunition, such as
smoke producing shells, was also produced, but was reserved mainly for signalling and for screening troops,
not for fighting. As a final note, ammunition and barrel qualities, due mainly to materials quality and
workmanship, were also a limiting factor in main gun accuracy and effectiveness. These arguments go a long
way towards explaining why the significantly larger 122mm cannons of the Soviet Union were inferior to the
German 88mm and the American 90mm guns at the end of the war.
PROTECTION
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The primary feature of a tank is its use of thick armor specifically designed to protect the crew and the
internal components from harm. Tanks were originally outfitted with just enough armor to protect them
from rifles, machineguns, and artillery fragments. It soon became obvious that the armor needed to
withstand attacks from antitank rifles and other tank guns. As these weapons were improved, the armor of
the tank was required to follow or become obsolete and vulnerable. Some weaknesses could be found in
every tank, including places where transmission or exhaust systems passed through the armor, the connecting
ring of the turret to the hull, hatches and viewports, suspension and tracks, and anywhere else that the armor
tended to be thin. These disadvantages were learned by every tanker in an effort to increase his life
expectancy on the battlefield and shorten that of his opponent.
Metallurgical developments prior to World War II included the development of face-hardened armor. This
involved taking a piece of ordinary “homogeneous” plate armor, and heating the front face to a higher
hardness than that of plain steel (normally compounded with nickel) alone. Although it was possible to
harden the entire thickness, it was soon discovered that this caused the armor to become brittle, and
shattered when struck by a solid shot of the same diameter as the armor thickness. Face-hardening allowed
for a harder, but more brittle, front face, which was backed up by a more pliable, easily worked softer plate.
As the war progressed, tanks were outfitted with thicker and thicker plates of face-hardened armor. A
sufficient thickness of face-hardened plate could also cause the solid shot of smaller guns to shatter on
impact, leading to further experimentation in ammunition design.
Tank designers in some countries, most notably the Soviet Union, realized that by making the armor steeply
angled or rounded it was possible to increase the apparent thickness. This had the additional effect of
increasing the likelihood that a solid shot would ricochet off of the hull, and reduced the amount of metal
required to obtain the same apparent thickness, thus decreasing overall weight and increasing mobility.
Rounded armor, especially for turrets, was often made by casting, which was cheaper and faster than welding
or bolting. Bolt-on armor was abandoned early in the war, when it was discovered that following an impact
the bolts flew off and bounced around the inside of the tank killing the crew. Welded armor was often used
when flat plates of angled armor were fastened together, particularly in vehicle hulls. The Germans also
tended to use this method to build their distinctively angled turrets and hulls. When they discovered the
inherent weakness of welded armor seams, they compensated for this by fitting the armor pieces together
using interlocking pieces, like a jigsaw puzzle. The angling of armor was also related to the discovery of “shot
traps.” These were places where the armor could unintentionally cause an enemy shell to ricochet into
another part of the vehicle, and were most often found around the turret. When this caused a ricochet into
the thinner armor of the upper hull, it could allow a relatively weak gun to destroy a very well
armored vehicle.