dents in the shoulder

Discussion in 'Reloading' started by dino foss, Apr 29, 2012.

  1. dino foss

    dino foss Active Member

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    This is happening to me more often than not. Im a beginner still, is this a sign of to much lube?
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    I have another question about pressure signs to the primer. Can anyone see pressure signs here? The first pic is a factory load and the second is a self load.
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  2. barnesuser28

    barnesuser28 Well-Known Member

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    yes you are using excessive lube and the hand load doesnt look to have any pressure signs based on the primer
    are you chamfering/deburring your case mouths?
     

  3. JeffVN

    JeffVN Well-Known Member

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    in order

    yes, you are likely using too much lube. You should probably run a few Q-tips up in there to get the potentially accumulating lube out of the die.

    Primers - they do not look flattened at all, no real visible smear on the case, no visible ejector marks on the case, so I would say no pressure issues visible from those factors. Cratering, by itself, is not necessarily an indication of over-pressure. Hard bolt lift, brass smear, ejector marks, in combination with cratering... is getting you much further down the road to over pressure.

    I would suggest you consider having the bolt bushed by some one like Greg Tannel, or someone else qualified. I have two rifles that have shown cratered primers from day one regarless of loan. I will be sending them to Greg who returns them very quickly for customers (within 2-3 weeks) according to folks that I shoot with who have used him recently for this very service.

    Jeffvn
     
  4. barnesuser28

    barnesuser28 Well-Known Member

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    just curios. what do you mean by getting the bolt bushed
     
  5. Outlaw6.0

    Outlaw6.0 Well-Known Member

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    I'll take a shot at this, & Jeff, if you had something different in mind feel free to correct me.

    When experiencing cratered primers with even mild loads, it can usually be (at least partially) attributed to excess tolerances between the firing pin & the hole in your bolt where the pin protrudes to strike the primer. The primer material will flow into the excess space, thus creating the "cratering" effect. I experienced this on my 6-284 before installing a PTG bolt.... even mild loads would crater, frusterating but it did nothing to defeat accuracy or case life, purely cosmetic in my experience.

    To remedy the situation, a competent 'smith will enlarge the firing pin hole in your bolt & install a bushing appropriately sized to the correct tolerances which should/will eliminate the excess space. If the primer material has nowhere to flow, it can't provide the "cratering" effect (with competent loading practices of course:rolleyes:)

    Hope that helps.
     
  6. Nimrodmar10

    Nimrodmar10 Well-Known Member

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    I thought shoulder dents due to excess lube happened when you size the brass, not when you fire it.
     
  7. Korhil78

    Korhil78 Well-Known Member

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    Haha..exactly what I was thinking. If that first pic is of a fired case, which is what it looks like, then you are having some issues inside the chamber. The only time that too much lube will dent the shoulder of a case is when you are resizing the case.
     
  8. JeffVN

    JeffVN Well-Known Member

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    Outlaw6.0 - you hit the nail on the head.

    Jeff
     
  9. sdeviation

    sdeviation Well-Known Member

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    I dont know if u was having same issue as me but my dents were created from a starting load of us869 in the 7stw behind a 180,,, i read somewhere it was called collapsed shoulder... The next batch of 3 with 1grain more and it stopped doing it...
    here is a pic of the 3 of them

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  10. barnesuser28

    barnesuser28 Well-Known Member

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    was this from below min loads
     
  11. sdeviation

    sdeviation Well-Known Member

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    i think there were a couple of things that contributed to mine...
    neck wall thickness uneven ,,,new virgin brass,,and most definatly to lite a load for this combination. all 3 dents were different sizes.
    would it do it again ? with fire formed brass neck sized probably not.