THE WORST APCR vs Up-Armoured Panzer IV | 85mm APCR vs Spaced Armour | Armour Penetration Simulation

The T-34-85’s 85mm cannon would normally have had no problem dealing with a Panzer IV, but how would its relatively weak APCR projectile fare against the spaced armour on an upgraded Panzer IV? Like many other designs of the era, the BR-365P Armour-Piercing Composite Rigid (APCR) projectile features a tungsten carbide core, however this core makes up only 13% of the projectile’s total mass. The remainder of the projectile mass essentially doesn’t contribute to penetration, meaning a lot of energy is wasted in by the design. For comparison, US APCR projectiles of the era had a core to projectile weight ratio of upto 50%. The BR-365P projectile was even an anomaly among Soviet designs, with the 45, 57, and 76mm versions having a more optimal ratio. This meant that the projectile did not offer much more penetration over the standard AP projectile. Compared to standard AP rojectiles, other downsides that all APCR projectiles suffer from are increased velocity drop over range (due to them being full-calibre yet lighter than normal projectiles), poorer performance against sloped armour, and shattering/fracture against spaced armour. The required materials often made them more expensive to produce as well. With these factors combined, the 85mm BR-365P projectile would only be a better option over standard AP rounds against a target with near-vertical ~125-160mm* armour at close to medium range. Nearly no German vehicles of the time would fit this criteria. *The standard AP projectile would easily penetrate anything below this range (with greater behind armour effects) and the APCR would not be able to reliably penetrate anything above it. The Panzer IV shown here is based on the Panzer IV D at the @thetankmuseum, featuring applique armour. The outer plates are modelled as 400BHN High Hardness Armour (HHA), with the base plate being 30mm of Face Hardened Armour (FHA) -600BHN front face, 350BHN bulk. Please contact for image credits.