Barrel thread question.

Discussion in 'Gun Project Questions & Gunsmithing' started by paulT, May 24, 2019.

  1. paulT

    paulT

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    Swapping out barrels with my f open rifle and i noticed one of the barrels seems to have double the amount of movement just before torqing to action compared to the other barrel, question is what is the acceptable amount of tollarance play there should be between barrel thread and action just before torqing tight.
     
    Last edited: May 26, 2019
  2. GenePoole

    GenePoole

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    Put a dial indicator on the action and with the barrel half-way screwed in, measure the movement at exactly 2.5 inches down the barrel from the action face. For every thou of movement, subtract 0.3 MOA.
     
  3. gunsandgunsmithing

    gunsandgunsmithing The best tuners and wind flags on the market Gold $$ Contributor

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    Do some research on thread classes and their respective tolerances. They all have tolerances and can be within spec while one is looser than the other. One can be too tight and be out of spec just as easily as it can be too loose. I'd much rather have one that's a little loose as opposed to tight. The shoulder does the squaring up of the barrel to the receiver.
     
  4. carlsbad

    carlsbad Lions don't lose sleep over the opinions of sheep. Gold $$ Contributor

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    Thread fit is not important. The most common mistake novice gunsmiths make is fitting the threads too tight. You don't want too loose a thread since that would be unsafe. but that isn't generally a problem.

    One thing I do see is barrels threaded for standard remington actions used on actions that have been trued and have oversize threads. these are VERY loose. I don't consider it acceptable but am not aware of an incident of one blowing out. Still, I strongly recommend not doing it.

    Tighten it up tight and any difference in performance is not associated with thread fit. --Jerry
     
    Last edited: May 24, 2019
  5. BoydAllen

    BoydAllen

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    Really? I disagree completely. The most accurate barrel that I have for my 6PPC has threads that are not just a little loose. they are very loose. V threads self center as they are tightened.
     
  6. boltman223

    boltman223

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    Yep, totally true, ive seen this at least 21 times.
     
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  7. GenePoole

    GenePoole

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    I forgot to put a smiley on my post.
     
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  8. Roeder

    Roeder Silver $$ Contributor

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    Could Mr. Poole be pulling our leg?
     
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  9. paulT

    paulT

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    Thanks for replies.
     
  10. Will Henry

    Will Henry

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    Would this figure be appropriate for a Savage, with a barrel nut, as well? Also, is peening the threads to reduce the slop an effective way to get this .3moa per thou back? I ask because it appears my Savage is set up to give me about 4 moa at best so I don't see any point in shooting it as is. WH
     
  11. carlsbad

    carlsbad Lions don't lose sleep over the opinions of sheep. Gold $$ Contributor

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    Will. that post was pulling our leg. Read the rest of the thread. Thread fit isn't your problem. Don't damage the threads, they are fine.

    sounds like you need a new barrel.

    --Jerry
     
  12. jr600yd

    jr600yd Gold $$ Contributor

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    Better than pulling your finger. Hehehe......
     
  13. Will Henry

    Will Henry

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    Would that be pulling our leg or legs? This is where these threads get confusing; a lack of clarity. I'm still not clear on just what I should be subtracting this .3 moa from. In fact, I suspect I should be adding the .3 moa; I'm just so confused. It's embarassing enough shooting a Savage and now I learn my threads suck. On top of that, I don't think my bolt head floats. WH
     
  14. Ggmac

    Ggmac Gold $$ Contributor

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    Savage bolt heads only float when using the original helium filled bolt body! Took me a lot of bolt heads fished out of the pool to find that out . Without the helium filled bodies the bolt heads sink like a rock , go figure . I guess it was in the fine print I didn't read .
     

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