Its beacause ur cold , do a campfire and it will be normal again.

I've had this issue too.

I don't think it's from being cold, as I once was bright green engerized, hydrated, and healthy, with no other status effects (cold or otherwise). I could be wrong, but need to do more testing.

Made a /r/dayz subreddit post on it: http://www.reddit.com/r/dayz/comments/2o65jl/shaky_aim_aka_parkinsons/

Anyone else have more information on this issue? Can dayz team comment on the issue?

Replies to my post on the subreddit have confirmed Necr0's suggestion.

If your gun is shaking, just a build a fire and warm up.

However, IMO there is still a bug here.

BUG --> You can have this shaking effect without any status message that you are cold.

Seems to me a player should be given a hint as to why they are shaking, and being cold/freezing is the one to do it. Just like when you are sick, the game informs you that you are sick.

You can have a fracture without the status being shown.
Try morphine or a splint.
Still the scope sway is overdone in this game, but is not a glitch.

I'm also having this issue. I don't think it's because of cold as I had a lot of warm gear on and used heatpacks to make sure I was warm; I'll try to find a thermometer to check my temperature. I also thought that it might be because I had fractured my leg a while before, but using a splint didn't help the shaking at all. I also tried using painkillers, which didn't seem to help. I then tried charcoal tabs and tetracycline just out of curiosity; they had no effect. I also made sure I was bright green energized, hydrated, and healthy with no status effects.

In response to Dillpickle, this is not scope sway. The issue is crazy shaking of the scope. It's like that the character has a massive current of electricity running through his body.

Jun have you tried a fire anyway?

The fire worked. I was kind-of surprised that the heatpacks didn't seem to have much of any effect though. Even so, it is a bit ridiculous how much my character shakes without the fire. I think shaking from the cold is a good idea, but I would only expect to shake that much if I was extremely close to freezing to death. I would also expect shaking to stop, or at least become controllable when I hold my breath.

Yeah it needs some tweaks in terms of relaying the status to the user, and I agree it should be variable depending on how cold you are. You should also be able to right-click zoom to reduce the shaking, since you could do that in real life to some degree.

Either way I'm glad we found a solution to fix it! Staying warm is more important than ever.