First things first… AP rounds shouldn’t have 100% chance of bounce at 63 degrees as it’s currently modelled in WT, not to mention the ridiculous 50% bounce chance at 60 degrees.
Here is AP simulation against armour at 65 degrees
Here is Russian 100mm AP(HEBC) penetration which also includes 70-75 degree penetration, but you know AP rounds totally bounce 100% of the time at 63 degrees (sarcasm)
According to this chart 100mm BR-471B can penetrate 110mm of soft Cast Armour at point blank range (895m/s) at 60 degrees.
2 Pounder AP (40mm, 1.08kg penetrator at 792m/s) penetrates 90mm of armour when it doesn’t deform.
Using 2 pounder as reference in demarre equation for 100mm BR-412 APHE. So the non blunt nose version without aerodynamic cap with 15.78kg penetrator (15.88kg with HE filler) at 895m/s
If 100mm BR-412 APHE didn’t deform against thick flat armour due to lack of piercing cap, it would defeat 273mm of Rolled Homogenous Armour at 0 degrees at point blank range.
AP(BC) slope modifier
100mm BR-412 APHE defeats 101mm at 60 degrees of Rolled Homogenous armour at 60 degrees at point blank range.
101 / 100 = 1.01 T/D Ratio
1.01 T/D at 60 degrees = 2.69 slope modifier
101 x 2.69 = 272mm
AP rounds at 60 degrees don’t deform and if the 100mm AP round didn’t deform at 0 degrees, it would defeat 273mm at 0 degrees.
Conclusion
100mm BR-412 APHE defeats 101mm (60) of RHA
100mm BR-412 APHEBC defeats 110mm (60) of Soft Cast Steel
I think that blunt shells don’t have better sloped penetration or some magical properties against sloped armour. Their flat noses give them utter garbage 0 degree penetration making their 60 degree appear much higher relative to 0 degrees giving us a false illusion of better sloped performance when it’s just the 0 value being atrocious.
As you might have noticed the 60 degree penetration for both the APHE and Russian Blunt Nosed APHEBC is underperforming. All AP rounds in War Thunder are basically missing 25% of their penetration at 60 degrees and they have 50% stupid bounce of chance at 60 degrees on top of that. It essentially artificially and indirectly buffs Russian tanks such as T-34-85 because tanks like Chi-To will have their 60 degree pen underperform by 25% for their AP rounds but they still have enough penetration to defeat them, however there’s 50% chance the round will bounce anyway and if there is additional horizontal angle the chance of bounce increases to 75% and by the time compound angle is 63 defeees for T-34-85 upper plate, you’ll bounce 100% of the time.
Same applies for M103’s M358 AP round vs T-55’s upper plate sloped at 60 degrees.
Note: Russian flat nosed APHEBC uses different slope modifiers which make them UFO at low T/D ratios. At normal high T/D ratios, both the AP and blunt nosed AP rounds are severely underperforming
Sloped Penetration of different rounds after fix
M6 37mm
M74 AP (0.87kg at 884m/s)
36mm @ 0m at 60 degrees
M3 75mm
M72 AP (6.3kg at 619m/s)
45mm @ 0m at 60 degrees
M1 76.2mm
M79 AP (6.8kg at 792m/s)
64mm @ 0m at 60 degrees
M3 90mm
M77 AP (10.61kg at 822m/s)
78mm @ 0m at 60 degrees
M3A1 90mm
T33 / M318 APBC (10.91kg at 853m/s)
81mm @ 0m at 60 degrees
M41 90mm
M318A1 APBC (10.91kg at 914m/s)
88mm @ 0m at 60 degrees
T15E2 90mm
T43 APBC (10.91kg at 975m/s)
96mm @ 0m at 60 degrees
T140E2 105mm
T182E1 APBC (15.9kg at 1067m/s)
120mm @ 0m at 60 degrees
M58 120mm
M358 APBC (23.1kg at 1067m/s)
135mm @ 0m at 60 degrees
On top of such penetration buff, you wouldn’t have 50% chance of bounce at 60 degrees and 100% chance of bounce at 63 degrees
That’s if gaijin had a basic clue about ww2 shell penetration and physics
