1. Please provide a reference to where the BATFE calls it a grey zone
2. Your statement of "you are not a felon" is incorrect. It is correct to say "you are not a felon under MA law, but are under federal law using the definition of felony proscribed in US Code for the purposes of firearms prohibited person status"
Please read the definition of Felon in 18USC922, section 20 in the definitions section:
(20)The term “crime punishable by imprisonment for a term exceeding one year” does not include—
(A) any Federal or State offenses pertaining to antitrust violations, unfair trade practices, restraints of trade, or other similar offenses relating to the regulation of business practices, or
(B) any State offense classified by the laws of the State as a misdemeanor and punishable by a term of imprisonment of two years or less.
What constitutes a conviction of such a crime shall be determined in accordance with the law of the jurisdiction in which the proceedings were held. Any conviction which has been expunged, or set aside or for which a person has been pardoned or has had civil rights restored shall not be considered a conviction for purposes of this chapter, unless such pardon, expungement, or restoration of civil rights expressly provides that the person may not ship, transport, possess, or receive firearms.
And then in 18USC922(g)
(g) It shall be unlawful for any person--
.....
(1) who has been convicted in any court of, a crime punishable by imprisonment for a term exceeding one year;
.....
to ship or transport in interstate or foreign commerce, or possess in or affecting commerce, any firearm or ammunition; or to receive any firearm or ammunition which has been shipped or transported in interstate or foreign commerce.
So, your claim that the "felon status" of a misdafelony in MA does not appear to have a legal basis.
Can you state what renders the above clauses in 18USC922 invalid? I mean court decision, precedent, etc. - not simply your assertion.