Overhaul of Gaijin calculator

On one hand the graph says it is overperforming against flat armor.
On the other the graph also says it would go through over 100 mm of cast armor at 60º (granted, protection limit, according to your comment).

I’ve seen a simulation that explains this better. Russian rounds had poor metallurgy as you said which caused them to shatter. It seems that this same shattering also made it so they performed better against angled armor, much like T33 APBC. It seems that their real life performance against angled armor came from the shattering characteristics of the round rather than the blunt nose itself.

Yeah, the Soviet blunt AP should more or less match pointed AP against sloped armor but I think it was better against under matching armor. I’m not entirely sure.

Just for reference, the T43 (T33 from the long 90mm) would pen 280 BHN 4” cast armor at 60 degrees at 3007 fps. That’s using army standard, not protection.

With some help, I gathered a bit of information about German APCR. Using my suggested changes, here’s how a few of them would look.

PzGr 40/43: 2.0 kg 36mm core at 1130 m/s is 313mm.
8.8cm PzGr40: 2.0 kg 36mm core at 930 m/s is 237mm
PzGr 40/42: 1.12 kg 30mm core at 1130 m/s is 252mm
7.5 cm PzGr 40: .90 kg 28mm core at 990 m/s is 192mm.
5 cm PzG4 40: .34 kg 21mm core at 1180 m/s is 169mm


I’ve made some updates to my changes. The APCR modifier was changed from 1.25x to 1.37x.


Comparing my results to some posted by Peasant in another thread shows the AP and APCR results are reasonable for Soviet style as well. The APC is known to overestimate many APC rounds but I don’t know of a reliable way to account for various cap sizes. It would have to be done on a round by round basis.


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Here are a few 90mm tables.

90mm M3 Early

90mm M3 Late

90mm T15


100mm D-10T chart. Replaced BR-412P with 3BM-8 APDS, based on limited info I could find.

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If anyone wants to know what certain rounds would look like, PM me the information and I will make a chart.

That is definitely true of wartime ammunition, American analysis of 45mm,57mm and 85mm APHE captured in Korea (Report ADA443218 which is publicly available online), they also consider the shapes used obsolete.

It’s interesting how the Soviets adopted capped AP by using German rounds as references, while the US dropped capped AP.

Is it possible that it was because the Americans realized that it was better to have more penetration at 60° in exchange for losing penetration at 0° while the Soviets continued to prefer penetration at 0°?
The bad thing is that it is not reflected in the game, since the APCBC drill at 60° the same or more than the APBC.

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That’s likely the case. It’s just something I found interesting.

That makes sense.

It must also be taken into account that the APCBC BR-412D ammunition is from 1953, so one could say that it was put into service quite late since the HEAT-FS of the 100mm cannon is from 1955.
Of all, I would not be surprised if they kept the BR-412A ammunition for the tanks destined for export, for example in the Yom Kippur War the arab T-54 and T-55 used the BR-412D ammunition, instead of the HEAT-FS or APDS, which were already available for the Soviet army.
That’s why I find it funny, the T-54 should have the BR-412A as the best ammunition, the T-54A could carry the BR-412D and the HEAT-FS, and the T-55 would carry the previous ones plus the APDS.El Tiran 4, being captured from the Arabs and maintaining the 100mm cannon, it would carry the BR-412D, I imagine that is why the cannon was replaced by the Western 105mm, apart of course from the fact of not having spare cannons and ammunition manufacturing.

How does Gaijin extract angled performance from this calculator? I would be interested in seeing the M103’s, T34’s, T32’s and T54E1’s angled performance with the modified calculator

Gaijin uses standard slope modifiers from WWII Ballistics, Armor and Gunnery.

M103 M358 APBC


T54 T182 APBC


T32 T43 APBC




Wanna see something funny?


The german 7.5cm PzGr.39 is rated to penetrate 100mm/0° at 650m/s. K DeMarre = 2103.
A 6,5kg 76mm shell (BR-350B) with the same K will pen 94mm/0° at 643m/s(100m). In game it pens 98mm/0°

Soviet magic ammo is better not only against sloped armour, but against thick flat plates as well. It’s better in every way, lmao.

I’m still convinced Gaijin based their calculator on Soviet rounds.


APCR carrier weight has a major impact on penetration. This boosts the performance of rounds with small cores in heavy carriers, like the Soviets. The uncapped AP penalty to represent Soviet APHEBC, but they also a get the OP slope modifiers to keep their performance.