I'm no stats Guru, but I threw this together in under 6 minutes.
I used Excel to take the top ranked 5 towns with over 2k population, and compared them to the lowest rank 5 excluding Boston. I did not have a great source of crime data for every town in MA, so I manually pulled the CityData.com crime index for these 10 places. 2 of the 5 pro-gun towns didn't even have data reported. Here is what I tossed together:
Community License per 1,000 Population Rank ▴ Crime Index
Pro Gun:
Shelburne 212.8 2,035 6 31
Huntington 198.3 2,219 10 n/d
Hardwick 185 2,649 17 120.6
Lanesborough 174.8 2,866 23 n/d
Cheshire 159.9 3,314 31 21.9
Anti Gun:
Amherst 15.5 35,565 344 144
Lawrence 14.4 70,014 345 327.2
Brookline 10.4 54,896 346 139.5
Chelsea 9.4 41,577 347 676.2
Cambridge 9.2 105,596 348 253.9