Common sense and analysis should dictate that already.
Let's just get on the same page for the first time. Banning guns would prevent
some gun crime. Equally, banning guns
could also increase other gun crime. This is deduced via mass shootings. Mass shootings statistically occur at high populace locations where the perceived threat of counter-attacks is at a minimum or perceived to be initially zero, ie schools, theaters, or generally "gun free" zones. So it is reasonable to infer that banning guns would potentially promote other incidents to occur given the lowering of the reasonable expectation of resistance.
None of that is specifically pro-gun or anti-gun. That's just logical inference and sourcing from historical events.
A note to make about the lapsed AWB of the 90's and perhaps more specifically California's AWB. One of the things most argued but highly supported via modern statistics is that population density along with area economics plays an unknown multiplier. That is to say, in modern population areas of over 50,0000 we see a non-uniform increase in violent crime. Under these studies the per capita rate does not apply uniformly. Equally, many studies have shown that if the poverty sectional lines are removed from large metropolitan areas, the crime stats per capita plummet. So in essence we have two things working against us, population density and poor economics.
I'm sure you're wondering what this has to do with the AWB. Well, it turns out that during the 90's we saw a dramatic shift in the US Economy. In fact, it was a stupidly good upswing. If you follow the US Economic trends, you will also see a similar trend in crime. (This is true anywhere.) While the AWB didn't have any real effect on booming the Economy, the Economy certainly has an effect on crime. That skews any attempt to use the data as it isn't singular.
The whole debate is far too often missing the big picture.
It's easy to say "ban X" when the alternative is "paying for y."
Side note...
http://www.nytimes.com/aponline/2014...lled.html?_r=0
Crazy shit happens evey-where. At the end of the day, kids are just easy victims.