Not enough, I'm sure, since most of the confiscations would have been from gangbangers with long rap sheets. But more importantly, of the convictions, how many convicts are still in the slammer even 12 months later? These mayors have no one to blame but themselves and their predecessors for the fact that their cities are overwhelmed by free-roaming career criminals.
I keep waiting for some 2A organization to put out a comprehensive study of just what percentage of "gun violence" is perpetrated by people who don't already have a criminal record. Every time some thug with a criminal record kills somebody with a gun, we hear all about how we have to "get guns off the street", but never any hard facts about the effect that getting the criminals off the streets would have.
oh come on, everyone knows that if we got all the guns "off the streets" all these criminals would go home make out resumes and get respectable jobs.
/sarc