T-14 Armata

[Husar]

I have a question for our millitary officianado's, the history books and articles I have read say that curved/rounded walls and armour was more effective protection against projectile weapons, so what has changed that it seems the more modern a tank the more flat and angular it's surfaces are?

Composite armor, different penetrator technologies I guess. Some say the modern penetrators can hardly be deflected anymore, so the attempt is usually to make them shatter and disintegrate. This is apparently also the reason that there are no shot traps on modern tanks because the penetrators usually aren't deflected anywhere due to their properties. There are still angled surfaces and I'd assume they still increase the amount of material in the way of the projectile and therefore help, but the relatively flat lower plates on many modern weestern tanks also made me wonder. Howevery, it could also be that these surfaces are less likely to get hit anyway, given that in many situations they would be covered by terrain and in an ideal situation the tank would be hull down, which is why the turret is often better protected than the hull I assume.