Unfortunately, the only way to solve the ability of people to travel to purchase guns in easier jurisdictions would be for the same laws nationally.  That isn't a great idea, rural communities are very different and have different needs than cities.

As for black on black crime, the percentages are about the same as white on white crime.  So it is more of a distraction than anything.  To a great degree, the communities most impacted by high crime rates need to work with the local PD to clean things up, unfortunately in Chicago especially, the PD is so corrupt that nobody wants to work with them.  NYC had similar problems in the 1970s and early 1980s, the mayor worked to clean up the PD, which in turn worked to get the population more willing to talk to the PD about crime in their neighborhoods.