-When should I use the AP Vs. the HVAP shells? The T-34's HVAP has considerably better penetration than AP up to ~ 1000 yards, slightly better up to ~1500 yards. While this is not as important vs lighter armored vehicles like M8 or M3, the flatter trajectory of the HVAP will help getting a hit on those usually fast moving targets.-Can an Ostwind destroy or at least turret a tank?It is at least possible on a Panzer IV, but only from very short ranges and from behind. It's difficult and rare. Of course you can still destroy track every other tank, but I would never deliberately up in an Ostwind to fight other tanks.-Is there a list somwheres with how many tank shells it takes to destroy structures?Yes, on the Aces High Trainer Corps Website (Topic "Projectile Strength Analysis")