The A13 Mk II turret frontal armor has the wrong thickness. All the A13 Mk II variants should have 30mm of armor in the turret front, currently the turret front itself in both A13 Mk. II is only 14mm thick. (see screeshots.) The Cruiser Mk IV A13 Mk. II and the Cruiser Mk IV A13 Mk. II 1939.

Both the A13 Mk II in War Thunder are labeled as Cruiser Mk. IV and all the Cruiser Mk. IV A13 Mk II should have 30mm of frontal armor on the turret front.
According to page 14 and 18 of Bellona Military Vehicle Prints series 20, the A13 Mk. II had 30mm of armor in the turret front while also keeping the ‘spaced armor’ of the turret.


Another source that also metions this is The war archives british cruiser of world war 2, page 15 of the book also says that the A13 Mk. II had a armor thickness of 30mm on the nose, glacis plate and turret front.

And yet another source is also Tank Power VOL. XCIII A13 Mk I/Mk II page 29 shows a armor scheme of a A13 Mk. II (Cruiser Mk. IV) and is also clearly shown that the turret Frontal armor should also be 30mm thick. (and not 14mm)

Sources:
- Bellona Military vehicles Series20 No. 79 & 80 - Page 14 & 18
- The war archives british cruiser of world war 2 - Page 15
- Tank Power VOL. XCIII A13 Mk I/Mk II - Page 29
What needs to be changed:
In order for the Cruiser Mk IV A13 Mk. II and the Cruiser Mk IV A13 Mk. II 1939 tanks to be classified as A13 Mk. II Cruiser Mk. IV the turret front needs to be 30mm thick and not 14mm.
Right now in game even the thickest parts of the turret front on the A13 Mk. II only gives a maximum armor value of 28mm.
So the turret Frontal armor itself needs to be increased from 14mm to 30mm
here’s all the sources:


