I want to put a pre-ban 20" A2 upper on a FAB 10 Kalifornia legal lower.  If you know about the FAB 10, you know it doesn't have a detachable magazine.  I know it's not a real AR, but it's as close as we can get here in the Peoples Republic of Kalifornia.

According to the manufacturers of the Fab10, because it doesn't have a detachable magazine, it can have any evil features you want.  It's not a post- or pre- ban lower, because there has never been a law about it written.  Everything I've seen and read points to this being accurate.  Kind of like you can trick out your pump shotgun -- not Semi-Auto, not part of the assault weapon ban.

If you are outside of California, that applies too, so anyone in the US can buy a FAB10 and legally put a preban upper on it.

It's expensive, but not expensive like preban lowers.

-Dan