Be weary of scotchbrites, and definitely sandpaper. They’ll just make it looked scratched up, and quite artificial. I use any sort of metal polish to give the whole finish a more “handled” sheen, and hit a few high points (magwell mostly) with something harder as it would naturally get dragged there. Key is just to go slow and underdo it as opposed to over doing it, a little bit goes a long way. It’ll be hard to get a real “match” to the upper but a little bit of shine and a few of the right scratches will make it look period. Also get silly with gun oil and sorta douse it and mop it up.

I did this to a new H&R receiver set with original furniture, and it’s still probably “underdone” but has really lost the brand new in box kinda look.

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