You can own most handguns here in Massachusetts with a few exceptions. The basic thing is that the Atty General in 1998 passed those moronic rules thus any handgun here before October of 1998 is legit.
As an example, you can buy a used TC Contender or Encore as long as it was in the state prior to 10/98 . I'd love to own a G2 but I can only get one if it is a carbine or rifle, not handgun.
I can buy a Freedom Arms Casull but it had to have been in the state prior to 10/98. WHat this has done is created an artificial scarcity, thus the prices have escalated artificially.