Don't you also need to control for large scale gun massacres at schools, concerts, parades, sports events etc.
Not really, those have always been around they just get more publicity now (except for Las Vegas which everyone is supposed to forget)....
There are also 'party shootings' a black (and to a lesser degree latino) phenomenon.... there's a party and someone gets mad for a really stupid bonehead reason, leaves, gets a gun, comes back and then randomly shoots into the crowd.... (hose and pose, it's called)
steve sailer noted that you can generally tell the race of a shooter by the casualty count... if the wounded greatly outnumber fatalities then the shooter is almost certainly black, if the number of fatalities is large then it's a white or East Asian shooter)
liberals hate that but facts is facts