I agree with easttex ^^ I have handled countless model 70s. Many had the screw, or the screw and the nut removed. None have had the nut "floating" in the dovetail, that I can remember.

Personally, I leave the screw out on a shooter. It certainly is not necessary. If you want to eliminate the possible pull on the barrel but want to avoid the look of an empty screw hole, remove the barrel nut and install front super grade swivel base nut on the inside of the stock. The threads are correct for the barrel screw - https://pre64win.com/products/super-grade-swivel-base-stock-nut

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