Why does stainless steel have pitting?

Discussion in 'Cleaning and Maintenance' started by MisterMcCool, Feb 20, 2013.

  1. MisterMcCool

    MisterMcCool Well-Known Member Supporter

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    I paid quite a bit extra for a stainless steel Springfield M6 Scout over the parkerized version because I understood stainless would not rust. What do you know? It has pitting now. I sent a letter to the manufacturer and they responded "keep it well oiled." Is this common?
     
  2. nitestalker

    nitestalker New Member

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    SS is simply more rust resistant not rust proof. I saw a Mdl. 66 S&W that was pulled from a creek. The Mdl. 66 had been under water for 2 years. The gun was as badly damaged as any other firearm left in the water for 2 years.:(
     

  3. Gonzilla

    Gonzilla Active Member

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    Minor pitting can be removed w 000 or 0000 steel wool. Some rub dry, others use light oil or WD40.

    Good Luck !


    I had a similar revelation about 15 yrs ago, ROA in SS had some pitting and it drove me Nutz ! (I never store a weapon dry - especially BP)

    Lesson Learned: Nothing is rust proof but some of these new finishes are impressive. I live on East Coast n salt water air is hard on steel.
     
    Last edited: Feb 20, 2013
  4. MisterMcCool

    MisterMcCool Well-Known Member Supporter

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    I live in Alabama and this is my truck gun. I didn't realize that even in the truck, it was exposed to humidity. It's not ruined, but p!$$3$ me off.
     
  5. 762

    762 Member

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    sand it down and throw a coat of duracoat on it or keep a rag in the car to wipe it down every now and then. i graduated from auburn, it's humid down there year round.
     
  6. c3shooter

    c3shooter Administrator Staff Member

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    As said- proper term is rust resistant, not rust proof. There are dozens of different alloys of iron, carbon, chromium and nickel used to make "stainless" steel. It would be possible to make a gun out of an alloy with so much chrmium in it that it would never rust in your lifetime- but would shatter like glass when you shot it.

    Called a tradeoff.
     
  7. Gonzilla

    Gonzilla Active Member

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    C3 - have you looked at Spyderco's H1 steel ? I've never tried it but buddy who sails a lot swears by them. He has a serrated model which is very effective w rope.

    A good after market finish is your best bet w firearms. Although, my HK w Hostile Environment finish has been remarkable. No pitting in 18 years...
     
  8. MisterMcCool

    MisterMcCool Well-Known Member Supporter

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    I just don't get it. I have stainless steel spoons and forks that have seen all kinds of abuse; water, acids, salt, detergents, dishwasher, etc. They don't have pitting or rust.
     
  9. JonM

    JonM Moderator

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    yes, but the alloys used to make your spoon and fork would make a handgrenade instead of a gun.
     
  10. MisterMcCool

    MisterMcCool Well-Known Member Supporter

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    That makes sense. Flatware is not as hard as gun metal.
     
  11. JWagner

    JWagner New Member

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    Stainless steel that is very good at resisting rust is a "300 series" alloy and it is not heat-treatable. So it is not usually strong enough for making a gun. It is non-magnetic; a magnet will not stick to it. The alloys that are suitable for making guns are the "400 series" alloys. They are heat-treatable, magnetic and not all that corrosion resistant. I got into this business of stainless steels when I was an engineer for a marine products company. Some stainless steels fall apart when exposed to sea water (oops!).
     
  12. ninjatoth

    ninjatoth New Member

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    Want to know whats funny,Here in Michigan where it's almost 100% humidity most of the year,my guns don't rust,but when my buddy from Colorado travels here with his guns,they start to rust quickly,even with the same model gun as I have,as if the metal is not used to the humidity.It's mind boggling how this can happen.
     
  13. primer1

    primer1 Well-Known Member Supporter

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    Believe it or not, steel is porous like wood. It even has a grain. Keeping steel well oiled will help keep the pores filled with oil, making it more rustproof.

    Bead blasting, I believe, pushes the pores shut with the surrounding steel, making it more rustproof.
     
  14. atrbertothy

    atrbertothy New Member

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    Not true. The higher the polish on metal the more rust proof it is. Polishing makes the pores smaller and harder for water to start rusting the metal. If anything the bead blasting will enlarge to pores.
     
  15. primer1

    primer1 Well-Known Member Supporter

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    so why then does bead blasting make metal more rust proof?
     
  16. atrbertothy

    atrbertothy New Member

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    Bead blasting don't make your plane gun steel rust proof. The rate at which steel will rust depends on a few things. One the weather were you live (the biggest factor), the chemical make up of the oils in your hands, and then the alloy make up of the steel. If you live in a dry area and you don't have what is called acid hands your weapon won't rust as fast as if you lived in a swamp.

    A good example is were I live in PA. I live by some wetlands. My 870 has a bead blasted parked finish and if I don't put oil on it it will rust but yet my Weatherby which has a mirrored finish has yet to rust. The finer the finish, the more rust proof it is. That goes for even for stainless steel.
     
  17. primer1

    primer1 Well-Known Member Supporter

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    Poor choice of words on my part. I meant to say more corrosion resistant, not more rust proof.

    I am aware of what causes corrosion, including the environment. I believe you might be confusing bead blasting with sandblasting. Bead blasting with glass or ceramic beads, does help to close the pores in metal, making it more impervious to salts, moisture, or acids, which cause corrosion.
     
  18. atrbertothy

    atrbertothy New Member

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    Not confused with the two. I do know which is which. Sand blasting uses aluminum oxide instead of glass beads and is far more course then the glass beads, but they both work the same and you will have a greater chance that pores will be enlarged and not closed.
    Like I stated about my 870. It has a bead blasted and parked finish. I know this because I did the finish, not someone else.
     
  19. Vincine

    Vincine New Member

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    Hmmm.

    I was taught to keep the stainless steel darkroom trays filled with water when they were not being used. This kept the air from getting to them and causing rust. Presumably the loose O molecules rose into the air and the O that was left was bound to the H.
     
  20. atrbertothy

    atrbertothy New Member

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    No stainless steel just takes time to rust. That is due to the alloys that are in the metal. Stainless is call slow rust in europe.