Bullet holes on a a character skinned mesh?

I basically want to achieve this effect http://i.dailymail.co.uk/i/pix/2013/09/15/article-2421049-1BD5EFCA000005DC-2_634x339.jpg , I have tried with small quads, but it works very, very badly when the decal has to be big, especially for the head, which is rounded. I s there another way to do it? It has been in games since the Half Life 2 era (2004). I cannot believe it's not standard in Unity...

The results are very diverging, from using stencils, to projectors with custom shaders, to this asset https://www.assetstore.unity3d.com/en/#!/content/13889 . None of those that I saw seem to "carve" a hole the way a (clamped) normal map in the secondary map of the standard shader would do, i.e. those seem to simply put a "smear" on the skinned mesh.

I could argue that "carving" a hole with a normal map is exactly what you do with the secondary map of the standard shader when you use normal map with it - you create a high-quality decal. The thing is this does not work with skinned meshes (or at least I cannot make it work).

Hi, I copied the link to an example in my original post in order to clarify. I put now an example from my project on the difference between what I want to do with projected normal map (on the quad to the right) vs on what I can do with projected shadow shader (on the avatar in the middle). I hope it's clear now http://i.imgur.com/VJIyIGW.jpg