do you think I could put my rem 700 bolt in the tumbler to take off the coating?

Its rem 700 s/a with still the same stock coating on it and its worn off a lot on the bolt but I'm wondering if I tumbled it if it would come off, and if its ok to do so

Media blast it, but be sure to protect your bolt face and lugs. I am sure there are places near you that would do it cheap. 20 minute job including prep.
 
Have someone bead blast it with 120 grit aluminum oxide. This is the prep that is done before Cerakote application. I have done this many times, including the lugs, and you will be fine.

Regards, Paul

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