oh boy here it comes for Connecticut...

"Under the legislative leaders' grandfather clause for high-capacity magazines, owners would have to submit to what lawmakers believe may be the first state registration procedure ever imposed on magazines, an informed source said Monday. The way it would work, owners would have to declare officially how many magazines they possess with a capacity greater than 10 bullets.

Under the new system, the high-capacity magazines – for example, a 30-round magazine – could never be loaded with more than 10 bullets outside the home, with one exception: The large-capacity magazine could be fully loaded at a licensed shooting range, the source said."

here