The engine should take into account the fact that it is physically impossible to hold the rifle in firing position "by the hip" or "sights up" when standing/crouching/proning very close to an object.
What the engine does, right now, is allow you to actually put the rifle through an object, even though you can't shoot through it.
So you carefully adjust behind an object and you see the sight clear on the target behind that object but when you shoot you hit the object.
There goes your surprise element...
It happens, basically when you lean behind a wall/rock but it also happens when you lie down on a ridge to shoot below. The sight is clear but the tip of the rifle goes through the scenery. You shoot but you hit the ground...
... the AI below shoots you back and kills you.
Maybe an indicator would do but maybe a more realistic solution would be to push back the soldier when he pulls up the rifle.
Remember: it can't physically enter a wall or a rock or a ridge so the sight CANT move where the tip of the rifle can't go. We need a "physical" solution to this very important issue (AI at elite level is very skilled and making such a mistake means sure death). {F22434}