According to Don Cook, the head armor and a match grade armor for the Marine Corps in the past. He says that when the M82A1A went out of Barrett that the scope rings were a Unertl ring. These rings were 1" rings and the rings were mounted on a base, to make a complete piece, that mounted on top of the SASR scope rail. Don says, that if you need more info try going direct with the Marine Corp Match Armor guys as they should have all the history on this. Hope this helps.
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