In the end of X-Men: First Class, Erik has knocked Charles down, and is directing the missiles towards
the warships and cargo ships in the water.
Moira, in an attempt to stop him, begins to shoot at him, and Erik deflects the bullets. Why didn't he just use his power to pull the gun from Moira's hands? If it was something about the effort it took to control the missiles, wouldn't it just take less effort, since instead of constantly deflecting many small pieces of metal, he could just take the gun and not have to worry about it. This also would have avoided the bullets accidentally hitting anyone.
Is there any reason why Erik wouldn't have taken the gun?