I think that there are already federal statutes specifically prohibiting the use of firearms in crimes, I'll try and dig 'em up when I get a minute.

I think this is the basis for the Project Exhile where the feds prosecute gang bangers and dealers for federal firearm offenses, rather than prosecuting them for the state crime. That way when they are convicted they are shipped out of state away-tougher for their families to visit and it's not Old Homies Day at Attica for the next 5 years instead they get tossed into a federal pen in Wisconsin with cheese smugglers.

This program has been somewhat effective in Rochester New York, which has a reputation of having more gun violence than the other upstate  NY (or central NY depending on whether you are from here or NYC) cities.