I had this happen to me for the first time over the weekend. Playing on one of the Wild Bunch 50-man servers, I had several separate incidents, all of which were EXACTLY what I expected.
Here's the scenarios:
1.) I'm lining up several shots on enemy troops on Kurland Kessel. I fire, nothing happens. I then hit the fire button again to rebolt, and end up firing again. WTF? This happened a few times.
2.) I was driving around in a Bren carrier, saw an enemy, and switched to the MG. In one case, my MG point of view was, apparently, the front of the barrel for some reason, and I couldn't even see the gun. The second time this happened, I was unloading on the guy, point blank, for like 5 full seconds. He managed to get a panzerfaust shot off, but for some reason was himself killed a split second AFTER he killed me. It was one of the most bizarre things I've seen happen. This was on Arad, by the way.
Both of these incidents played out exactly like previous versions where tanks would fire "blank" rounds, or in the mod where I'd target a guy, have him lined up PERFECTLY, completely filling my sight, fire, and then he'd turn around and shoot me. Also, the old thing where when you fire and let go of the fire button, your last round shoots where the barrel was pointed a split second after the fact is going on.
All of this makes me think that servers now have too much info to track and SOMETHING is placing more strain on the servers than before. It could be the new "NP" system, or it could be something else. I don't know. It's definitely an issue of client-server communication, though. It's not FPS drops. I don't know what's triggering this, but when the TWB servers are having problems, you know something's up.