They are made by Mossberg. Charter Arms was making them in their own factory in the U.S. and selling them as the Charter Arms Raptor. Mossberg bought Charter Arms and renamed the rifle. They are still made in the U.S. but I don't know if Mossberg moved production to another facility or makes them in the former Charter Arms factory.
I have seen some comments on other forums that the performance of some early Raptors disappointed owners and that production quality from Charter Arms wasn't as good as it should have been. I haven't seen many reports from owners of Mossberg ATR100s, but the few I have seen have all been been satisfactory.