I noticed that most of the time, when I use any explosive inside or outside of VATS, the target do not take any damage. In VATS, when I use any kind of explosive the enemy health bar is empty and take no damage at all. Outside of VATS I can fire 10 missiles on a target an nothing happen, no damage is taken. After a quick search on the web I see that this bug was reported a long time ago and it was not fixed in the latest patch... What the hell are you waiting for? If you can't fix that kind of thing, why not just remove all the explosive weapons since it seem to be a tremendous task to fix it.