Thanks for all the info. The forearm on mine is roughly the same, 8 7/8" from the receiver, with the center of the 2 lines 7 1/4" from the receiver. Here are some pictures to go along with Calhoun's. I would think the measurements would be close as they are for the same mount, but I could imagine quite a difference in them for the eye relief of a scope, if not put there from the factory.
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