Ignore the AG. I see mostly ARs at our CMP matches and when people are shooting on the rifle ranges. She said that we're all felons for having possessed them since 1994 but she won't prosecute us, so it is business as usual at the range. As of now it is only dealers who are screwed. Anyone else hiding their ARs in Mom's basement and afraid of going to the range is just paranoid.
I am guessing that banditone is asking what is a Mass resident to do if they don't already have an AR-15 and want one to compete in 3-gun style matches. In which case I would say that he should find a MA resident who is selling either a lower or a complete rifle in a private sale and obtain one that way. Preferably a stripped lower since then he can build it up to his exact specifications for competing rather than having to modify an existing rifle.