FYI, MA and Shotguns
As far as I can see in Mass Gun Law, Chapter 140 Section 121...
An AW is a semi-automatic.
"the term assault weapon shall not include: (i) any of the weapons, or replicas or duplicates of such weapons, specified in appendix A to 18 U.S.C. section 922, as such weapons were manufactured on October 1, 1993; (ii) any weapon that is operated by manual bolt, pump, lever or slide action"
So, the term AW is Not applicable to a Pump shotgun.
This term Large Capacity Feeding Device does apply, so an LTC is needed.
"Large capacity feeding device'', (i) a fixed or detachable magazine, box, drum, feed strip or similar device capable of accepting, or that can be readily converted to accept, more than ten rounds of ammunition or more than five shotgun shells"
The term Large capacity Weapon does Not apply to pump shotguns...
"The term "large capacity weapon'' shall be a secondary designation and shall apply to a weapon in addition to its primary designation as a firearm, rifle or shotgun and shall not include: (i) any weapon that was manufactured in or prior to the year 1899; (ii) any weapon that operates by manual bolt, pump, lever or slide action"
(the above is taken right from the laws; I am no lawyer: interpret it as you see fit)