I have this suspicion that the visible shots and the ones that count are two different things. It's a Bf2142 engine thing, in that case. Happened in Bf2, too, come to think of it.
Also if you insta-prone and shoot at someone right in front of you, you'll sometimes see the shots go right through them without registering. So again, I think the visible shots and the shots as handled by the server are two different things, and that it's a bug/limitation similar to how you can hit a fighter without the hit registering.
"One of the bitches actually gave birth while she was attacking, and her puppies joined in on the carnage."
--the awesomeness that is Boatmurdered.