Although the German Military had known about the T34 for quite a long time, it wasn’t until they encountered it in combat that they realised how much of a step forward the Tank was compared to previous Soviet designs.
Most noticeable was the glacis Front plate of the Soviet T-34, which helped alleviate the impact from enemy weaponry. Even with these advances the T34 was still outgunned and less damage resistant compared to its German counterparts. but the sheer quantity that they were able to produce the tank (almost 1200 a month at certain points in the war), Gave the Soviets a massive advantage when it came to the number of tanks they could deploy at any one point.
The initial version of the T-34s was equipped with a 76mm main gun, however it proved to be inefficient against their main rivals, in particular Tiger and Panther tanks.
As a result, upgrading the firepower of the T-34s became essential to the Russians ability to fight back against the invading Germans.
Eventually the Military ordnance department upgraded the T34 to a 85 mm main gun which proved far more effective, and to distinguish the T-34s with different main guns, it was named T-34-76, and T-34-85 respectively.
