I dont see it posted about much, but everyone should know its true. Several times I have blown up a C4 right under 1 or multiple enemies and it doesnt affect them at all. I'm not talking about flak jacket, I'm talking about literally it just not registering at all. It's been this way since release, but C4 is so good that I have been kind of ok with this issue.
Today though I had 3 incidents where I C4'd and saw the explosion right under 3 enemies running towards me. I figured it could be lag, but then watched THEIR killcam and it shows them running together, and an explosion going off right on them.. and there screen doesnt have any damage indicated at all. It's just ridiculous.. I cant believe it hasnt been patched yet.
If I play for an hour it probably happens 3-4 times within that hour. I use C4 like crazy and rush the entire match though, so I dont know if that may play a role in it. Maybe if your character is moving forward and you throw a C4 its late on registering or something? I have no idea. It happens to me with double/triples non-freaking-stop though. I get a lot of double and triples still, but not nearly as many as I should have.
I can say I have never had that problem.... Only issue I have come across to tossing far away, blowing it up then I die and its says mistakes were made, then on killcam I didn't even throw it far it landed infront of me then I blow it up.
Maybe the problem is the same, the animation is going further then it looks, so when you blow it up its not actually one them.
^ sadly you wouldn't know the animation went further then it actually went, unless you die after throwning it, or you can see the coding used.. Kinda like when you get hit markers, but in the killcam you never even shot him.