In my estimation, there is a little less than 50/50 chance of a "grandfathered" semi auto ban passing the legislature this session or this year. The chances of a full blown legal ban on the sale, possession, transfer and use of semi autos, at any rate, are fairly slim.
Any successor to Daley's mayoral seat, under any political circumstances, will be probably be Mexican or possibly a black. Any representative of this divisive group will also be, much like Daley, a liberal socialist, and will most decidedly be very hostile to private gun ownership.
Crime fighting in Chicago means suppressing and prohibiting the general citizenry's firearm rights and overall civil liberties. Going after the actual purpetrators of crime is tantamount to discriminating against your own voting constituancy, which is political suicide in modern day Chicago.
Never underestimate the pro criminal lobby. They exist in high places.