On the topic of the armor of the Puma, (@Smin1080p_WT will be interesting for you as well);
First:
The armor in front of the powerpack should be significantly thicker (this photo is from the Puma prototype currently located at the Munster Panzer Museum, as such it’s missing the additional layers of the production vehicle):
Here’s a napkin calculation of armor density if it were built from pure RHA:
We know that Pumas armor, on top of the base hull is increased by 43 t - 31.45 t = 11.55t
The side armor is ~4.2m^2 on the right side and 450mm thick.
The side armor is ~5.0m^2 on the left side and 450mm thick.
The roof is ~10.1m^2 and mostly spaced / rubber armor.
The turret armor is a total of ~2m^2.
So in total thats an area of 21.3m^2 where the protection is increased.
Assuming the armor is perfectly evenly distributed that would net us ~542kg / m^2.
542kg / m^2 of pure steel (@ 7900 kg/m^3) would be equal to a 1m^2 steel plate with a thickness of 69mm.
The base armor is 320kg/m^2 = 40mm steel (required armor against 14.5 API).
So combined the Pumas all around avrg armor should be:
40mm + 69mm = 109mm, if it would be build out of pure steel.
However, what needs to be kept in mind is that RHA is significantly less weight efficient than modern composites, and the Puma still took on additional ~11 tons in pure armor when going from Standard A to Standard C.
The protection of the hull’s side (at an angle of 0 degrees) should be (at the very least) ~110mm instead of the current ~70mm.
At the moment, the armor of the vehicle is nowhere near close enough to the estimated values, neither for the S0, nor for the VJTF.
Two:
This graphic is baased on this photo:
Spoiler
Amount of steel used in the construction of the upper plate is:
40 + 5 + 7 + 5 + 7 + 5 for a total of 69mm of RHA/high hardness steel, as such, the upper plate, when fired at from an AoA that is neutral to it, should be equal to 69mm RHA + (~6mm rubber * 0.3 KE) ~2mm of rubber, achieving ~71mm against KE projectiles. Does it though? Far from it:
It can only do 46mm against KE, i.e due to the combining (by Gaijin) of all of Puma’s armor layers into one to simplify the model, it has resulted in the protection being lower than its steel alone should offer (have any of you ever seen RHA that has a lower KE modifer than 1.01/1.1? I haven’t. Unless of course, Gaijin thinks that PSM/KMW used ductile steel in the construction process).
Now, at an angle, this 46mm turns into ~130mm RHAe against KE when the vehicle is shot at from the front, we can calculate the modifier that governs this: it’s 2.82608695652 (130/46)
If the upper plate had been performing as it’s supposed to (i.e ~71mm of KE at an AoA of 0), then the upper plate should offer protection of about ~200mm KE instead (71*2.82608695652).
edit: (not to mention, it is highly likely Puma’s armor follows the same philosophy as Leopard 2s wedge armor, so the first two layers are meant to break KE projectiles apart, with the rest being there to absorb the fragments and such, it is very possible that the KE protection should be higher than ~200mm RHAe, to what degree I can’t say, yet).