A couple of points:What, if anything, prevents an MA resident interested in obtaining, say, a bunch of new Glocks, from simply acquiring an FFL and buying them in NH, or direct from Glock?
Getting a Type 01 FFL is a pain in the ass and is not doable by the average person. These days you have to show intent to run a legitimate business to get one, among zoning considerations and other things, and in MA there's a second permit that's also required from the state/local level. Yes, you could do this, and it would work. The thing is
though is it is the equivalent of purchasing an Abrahms tank to crush a fly.
WRT buying one out of state, when the glock hits the MA dealer, the MA dealer will (typically) reject it if it is not compliant. All interstate handgun sales must go through an FFL in the buyer's state of residence (as required by FEDERAL law) so this means that if an MA resident buys a Glock somewhere and transfers it to MA, most MA dealers will
not transfer it to the end MA buyer if it is not compliant.