The three most common properties of dragon scales are:
- being lightweight
- just plain resistance
The first two are simple: by making the scales out of a substance similar to nacre, and by making that substance into a foam, dragons could effectively resist any change in temperature, and if they do need to warm up/cool down, they can just open their wings.
Plain physical resistance is harder, especially in a fantasy world with self-replicating Anti-materiel rifles and a pretty much extinct ATF.
So, the key problem with bullets is that they go way faster than any muscle-powered weapon, which ultimately allows them to ignore the cohesion of the armor even more.
Now, since the scales are much thicker than regular but only because they're mostly air. How can I make them more bullet resistant? And so, of the pool of natural bullet-resistant materials, does this limitation make one particular solution stand out as the best?
What's the best?
- RHA equivalence, the higher the better (basically defensive value).
- Density, the lower, the better.
Note: Of course, dragons could always resort to cheesy tactics, such as sticking shed scales back on themselves, if they ever needed to.