First Welcome! Second take the stocks off that baby, then soak in a sealed container for a couple of weeks in 1/2 plain/cheap/non-synthetic ATF and 1/2 acetone.

Take it out, give it a good scrubbing with a toothbrush. Hit any rust left—there won’t be much—with BRASS wool.

Then you will have a new gun.

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Possum—The other white meat!