More info on machine guns in MA... Found this link to the Mass General Law http://www.state.ma.us/legis/laws/mgl/140-131.htm
That is the part of the law regarding LTCs and such. If you scroll to the bottom, the last half page or so regards machine guns.
(o) No person shall be issued a license to carry or possess a machine gun in the commonwealth, except that a licensing authority or the colonel of state police may issue a machine gun license to:
(i) a firearm instructor certified by the municipal police training committee for the sole purpose of firearm instruction to police personnel;
(ii) a bona fide collector of firearms upon application or upon application for renewal of such license.
(p) The executive director of the criminal history systems board shall promulgate regulations in accordance with chapter 30A to establish criteria for persons who shall be classified as bona fide collectors of firearms.
(q) Nothing in this section shall authorize the purchase, possession or transfer of any weapon, ammunition or feeding device that is, or in such manner that is, prohibited by state or federal law.
(r) The secretary of the executive office of public safety or his designee may promulgate regulations to carry out the purposes of this section.
Still can't find any info on other sorts of NFA items...