chamber chroming

Discussion in 'Gunsmithing' started by sigsupermatch, Aug 30, 2013.

  1. sigsupermatch

    sigsupermatch Well-Known Member

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    Does anyone know of a place that chromes chambers? I bought a Rem 7400 and it appears someone got a little too aggressive in cleaning a bellied the chamber about .003.
     

  2. J E Custom

    J E Custom Well-Known Member

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    Chrome lining the chamber will not take out the belly, It will only apply about .001 Thousandths to the whole
    chamber and cost a ton.

    Depending on the caliber, The best thing to do to a semi auto it to re chamber to an AI version
    of the cartridge.

    This will straighten out the chamber walls and increase powder volume and performance.

    If it were a bolt action I would recommend setting the shoulder back 1 full thread and cleaning the chamber up and back to spec.

    J E CUSTOM
     

  3. sigsupermatch

    sigsupermatch Well-Known Member

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    Thanks. Would you know of a gunsmith who could cut the chamber to the 3006 AI? That sound like a option that would work for me.
     
  4. J E Custom

    J E Custom Well-Known Member

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    Any good gunsmith can do this for you if you have one near you, talk to him about it. If not there are several good ones that are sponsors on this site that you could send it to.

    J E CUSTOM
     
  5. shortgrass

    shortgrass Well-Known Member

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    Your Rem 7400 cannot be re-chambered for the A.I. version. Ackley Improved has a shorter headspace dimention than the parent cartridge.
     
  6. MontanaRifleman

    MontanaRifleman Well-Known Member

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    Is this a factory barrel? Not sure I would invest any $$$ on a factory barrel. I would be more inclined to rebarrel with a good quality after market barrel.

    If you want to keep the barrel, I would think setting it back about a 1/4" to !/2" would take care of the belly.

    Definitely get it bore scoped before you spend anything on it.
     
  7. J E Custom

    J E Custom Well-Known Member

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    I would agree with you 100% if it were a screw in barrel with the recoil lugs in the receiver But
    The 7400 Remington is an automatic and has the recoil lugs machined into the barrel. re barreling with a custom barrel would be very expensive so In my opinion the best way to fix the problem
    would be to enlarge the chamber to an AI or replace it with a new factory barrel.

    I don't know how much a factory barrel will cost and it would probably have to be sent to Remington
    to be installed and head spaced.

    Just a comment for what it's worth.

    J E CUSTOM
     
  8. shortgrass

    shortgrass Well-Known Member

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    Ok,, set it back. What about the gas port location? So, enough money can fix anything, but spent on a Rem ington 7400? I don't believe I've ever seen one , in any caliber, that'll do much more than shoot a shotgun pattern.
     
  9. Trickymissfit

    Trickymissfit Well-Known Member

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    first of all, to chrome plate the chamber is going to be a bear to get right. Yet it can be done. You simply can't put three thousandths all the way around on the barrel. The chrome won't stay put (probably won't if done right as well). You need a minimum of a .008" coating after it's finished out, and .012" would be a lot better. The idea of doing it will end up being very labor intensive. You simply can't just plate a small part of that chamber on a whim. It will involve cutting the chamber about fifteen to twenty five thousandths oversize (all the way around). Then you must mask it off (they'll have a lot of not so nice words for you by the way), and copper plate the areas to be chromed. Then you go back in there and re mask the chamber area again, and strip the remaining copper. Now you are ready chrome plate the chamber.

    Ok now you got this plated up barrel, so how do you fix it? Forget using a reamer or a lathe. Stuff is too hard. You'll need to grind that chamber, and now the cost rises like the Apollo Moon Rocket! Plus I'm not sure they would ever get the shoulder to case body area right. But to further mull up this grand scheme, the chrome won't stay put in the chamber. The heating and cooling from shooting will assure this issue alone.

    There is a really nice spray metal process that actually is machinable . Also expensive. I've used this process in the past, but it's also not recommended! The other way is electroless nickel. There are two kinds, and one plates within fifty millionths, but the chamber is bad.

    I'd simply forget repairing the barrel! Also are you sure the chamber is actually in the form you say? In an auto, the chambers are often cut differently than a bolt gun. They're usually oversized and tapered to aid feeding. I'd send the rifle back to Remington, and let them fix it. I can't see how anykind of a brush could do that much damage (maybe stainless steel). If the rifle shoots OK, I'd just live with it (most I've seen shoot 1.5" groups or worse)
    gary
     
  10. Hired Gun

    Hired Gun Well-Known Member

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    How did you determine it is .003" oversized?
     
  11. sigsupermatch

    sigsupermatch Well-Known Member

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    Ok, here is the info on the rifle. Starting with a clean rifle. The first cartridge fired will ejectand reload fine, second fired the extractor will pull so hard to get the spent case from the chamber it will slightly bend the lip on the head of the case. each case after that will get bent more until the extractor will rip a notch out of the case and not extract the spent case. Usually the third or fourth case will not eject. All factory loads.
    Case info is as already stated the rim is progressively deformed. In addition looking at the case from the side starting at the head the first inch is clean as new, the remainder of the body is discolored. The mouth of the case looks normal. When I measured the case it appears the it is bellied in the middle (discolored area) more that the end (cean area) by around .003.
    The reason I am trying to fix this thing is my son requested this exact rifle as his first deer rifle. I had one as my first big rifle as well which he did not know until after he choose it.
     
  12. FEENIX

    FEENIX Well-Known Member

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  13. sigsupermatch

    sigsupermatch Well-Known Member

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    Thanks. Only thing is it's not a problem with the barrel. The gun shoots great as a single shot. The problem is the chamber.
     
  14. shortgrass

    shortgrass Well-Known Member

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    THE CHAMBER IS PART OF THE BARREL!!!! You cannot seperate the two!