The reload times are correct. Baiscally the T-34/76 had a really, really bad ergonomic setup for the loader.
In most tanks the ammunition is stored in the turret and the turret has a floor, so that people standing in the turret rotate with the turret.
In the T-34/76 it only had the first 6 rounds in the turret. The rest of the ammunition was stored in ammo boxes that make up the floor. As the turret turned the loader had to shuffle around on the ammo boxes to keep up with the turret's rotation. To load, after the first six rounds, he had to remove the empty shell, bend over, open an ammo box, take a round out (and maybe put the empty shell from the privious round into the vacated space), close the box and then place the round into the gun.