I love gun nuts bring out the same stats and figures every time, even when they fail to prove your point. Kennesaw has mandatory firearms yet is only half as safe as my hometown, which is about the same size.
Kennesaw gets a 35 out of 100, with 100 being the safest:
http://www.neighborhoodscout.com/ga/kennesaw/crime/
My home town gets 72 out of 100:
http://www.neighborhoodscout.com/ca/lincoln/crime/
Thus, by your logic, this town would be better off if they didn't have this firearm law.
You are cherry picking stats because the NRA did research on this and loves to tell this story, yet I just compared it to home city and it's much safer here - plus, I don't have to worry about my neighbor shooting me if I decide I need to borrow some butter after dark.