Just an FYI,
If you go to a gun dealer to purchase a new firearm. You will have to fill out an ATF Form 4473. When answering question 11e, (See form below) you need to pay attention to what it’s asking. The Federal Government does not care that Massachusetts has legal Marijuana Statutes. They still consider it illegal. If you check off yes on this form and the dealer processes your paperwork you have now become a prohibited person from owning a firearm.