Got my new Marlin 39a and while the lever cycles great, it could be greatly improved upon. So, I decided to take it apart to see what was up. To my surprise, there was A LOT to be improved upon. Machining marks EVERYWHERE, gritty surfaces, as well as rough grinding marks that looks like they ground the part to fit right, not taking the time to finish it up. Anyways, my plan was to bust out my dremel and polishing pads/compounds as well as some super fine grit sanding disks and to go to town touching up what Marlin didn't. Afterwords, my plan was to apply some cold blue to refinish what I've worn off. So long as I don't go nuts with material removal, do you suppose I could really hurt anything by smoothing and polishing the flat surfaces that slide against each other? From my perspective, I could only improve on what I've already got. Thoughts? Shitty pic of firing pin. grinding marks circled:
I like to shoot a gun grit and all for a while, then take it apart and look at mating surfaces. Rough spots will be obvious, as they will be worn. Polishing is generally an easy way to make a gun feel better, and sometimes can provide real dividends in performance (CZ's are a perfect example here). You can certainly fuck stuff up though, so know what you are getting into before you go hog wild with a Dremel. Remember that polishing is smoothing, not removing. Go slow and you'll be fine.
When working on your gun you should always keep all ammunition and dremels safety locked up in another room. If you're really jonesing to polish, start by hand, you're less likely to fuck it up beyond repair and most of the time, it's all you need.