There are two avenues here to consider, both of which would be violations of MGL 140 131M
- Does it have a Large Capacity Feeding Device (15 rds or 3x5 rds)
- Is it an Assault Weapon
Most people seem to focus on question #1. I don't think this is a zero risk proposition to say it is 3x5. Yes, you have to take a manual step to index to a new 5. Yes it is like a device that attaches two AR mags together BUT I CAN STILL TAKE THOSE MAGS APART. The device that holds the rounds is a single formed piece of plastic that holds 15 rounds. Let us just focus on that. One piece of plastic, 15 rounds. The rest does not matter. You can't escape this. One piece of plastic. 15 rounds. Had they made the magazine as 3 separate 5 round tubes with something holding them together, I MIGHT seen a argument for it being 3 5 round mags. Maybe
Question #2. AWB for shotgun says semi auto with at least 2 of
- folding or telescoping stock
- pistol grip that protrudes conspicuosly beneath the action of the weapon
- a fixed magazine capacity in excess of 5 rounds
- an ability to accept a detachable magazine
This has fixed capacity in excess of 5 rounds, dewitt 15 rounds. It has a pistol grip. Again, you can make magical thinking arguments that it is not a pistol grip because it has something attached to it or that its a bullpup so the pistol is not below the action (then how does the trigger work?). You can try the "its 3 5 round mags" argument again. I think this is all fail. It is an assault weapon.
Anyone who knows me knows I will try and find ANY legal work around to sell/transfer want people what that is lawful for me and them. The Tavor 12 is a pair of felony charges waiting to happen (double violation of 140 131M).