Head Spacing?

Discussion in 'Mosin Nagant' started by K.H., Aug 7, 2008.

  1. K.H.

    K.H. G&G Newbie

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    Hey guys I have a question regarding headspacing on a mosin,

    If the numbers match on the bolt and reciever should It still be checked?, The bolt body was converted to a sniper bolt but it is still the original bolt body, and it cycles the bullets fine and has no problems, I have not shot it yet though, would it be unsafe to shoot it without having it checked?, and if so could I check it myself somehow? beause there are no gunsmiths around here. K.H
  2. texnmidwest

    texnmidwest Sir Loin of Beef Forum Contributor

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    Better safe than sorry. Buy a go or no-go gauge. Follow the instructions. Cheap easy way to check all your Mosins.

    Also, make sure the firing pin is set properly. That is the main danger. It should hit the shallow mark and clear the taller mark.
  3. K.H.

    K.H. G&G Newbie

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    The firing pin is set properly, and where could I get one of those gauges?
  4. texnmidwest

    texnmidwest Sir Loin of Beef Forum Contributor

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  5. stevensj2

    stevensj2 G&G Newbie

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    If it previously shot OK, and only the bolt body was replaced, and the bolt head is still original, it ought to be fine.

    Although it could be dangerous, it is likely safe.

    My bolt matched, and the firing pin protrusion was safe. But because it was a new gun to me, my first shot is always from the hip.

    I also used a rubber band to hold a white peice of paper around the receiver/bolt while I shot. Doing this allows me to see if any powder/gas is being expelled (indicative of poor headspace). No black residue on the paper, and no exploding gun, means everything is safe.

    (That is by no means a suggestion over gauging - but of all the Mosin posts here, I've never heard of any problems.)
  6. wjkuleck

    wjkuleck G&G Newbie

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    In the Mosin-Nagant 1891 design, so long as the same bolt head is used, the headspace remains invariant regardless of the bolt body used. That doesn't mean that the headspacing was right in the first place, just that since it's the bolt head that locks into the receiver, the bolt head defines the headspace dimension.

    Regards,

    Walt
  7. SwedeSteve

    SwedeSteve Freedom Zealot Forum Contributor

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    Get a Field Gage from Brownell's. It ensures the headspace is within safe specs. Brownell's part # 319-000-004. $26.00
  8. wjkuleck

    wjkuleck G&G Newbie

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    That's what the GO and NO-GO gauges do. FIELD is don't shoot it unless you positively have to. If your bolt closes on the NO-GO, but not the FIELD, the rifle is out of spec on the long side and should be repaired immediately. In exigent circumstances, if you're feeling lucky, have really good brass and really, really need to shoot, OK, but get the headspace corrected ASAP.

    One way for handloaders to "correct" rimmed or belted cartridges is to size such that the shoulder acts as the cartridge "stop," rather than the front of the rim.

    Regards,

    Walt
  9. marion57

    marion57 G&G Newbie

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    I want a count of hands on how many here have ever seen in person a mosin that didnt pass head space? I have handled and shot a bunch and have yet to find one with bad head space..I would bet that the only man on here that ever even saw one whith bad head space is probably Mooseman
  10. samuel

    samuel G&G Newbie

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    If you have any fired brass it would show if there is a headspace problem.The body would be bulged considerably.(.006" or more) sam.
  11. Rex in OTZ

    Rex in OTZ G&G Enthusiast

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    If a fella could fit a know thickness between the bolt and the cartridge case that would give you a idea of the free play between the bolt and cartridge rim so x amout of freeplay should = a renge of being safe or not.
    I used a disc of typeing paper that mic'd at 2.1/2 thousandths and inserted in the bolt face and attempted to close the bolt on a live round, what I learned was the bolt would start to bind and wouldent close "so what I did know" was that the free-play was "Less" than 2.1/2 thousandths plenty good for what I was looking to find out. yes paper does compress but i did find out in the ball park what I was looking for
    now I If was up to 2 or 3 disc's of paper I'd have to get headspace gage from Anchorage or Fairbanks and have it sent out to the bush, Im not going to send in a $80 rifle to town to get it check'd for the cost shipping & handling I could buy a whole nother rifle.
  12. SwedeSteve

    SwedeSteve Freedom Zealot Forum Contributor

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    I've never headspaced any of mine and have shot all but one. Eventually, I'll need the gages to assemble a rifle I am building. A field gage tells you the rifle's headspece is within safe limits.
  13. marion57

    marion57 G&G Newbie

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    If your rifle has been arsenal refurbished it has had the head space checked already
  14. WW2Junkie

    WW2Junkie G&G Newbie

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    Mosins are not known to have headspace problems. As mentioned earlier, most were refurbished and checked good. Enfields on the other hand, check 'em! If you want to check headspace get a "field" gauge. If it passes that, you're good to go. Using "go" and "no-go" gauges are extra expense and not needed unless you are building a gun.
  15. SwedeSteve

    SwedeSteve Freedom Zealot Forum Contributor

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    ^ I agree.
  16. Rex in OTZ

    Rex in OTZ G&G Enthusiast

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    There is coin head space gages for rimmed rounds that sell for less.
  17. K.H.

    K.H. G&G Newbie

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    Mine is a refurb so that means I dont need to check it?

    I was just wondering because some friends of mine told me to have it checked.

    P.S. Thanks for all the help guys.
  18. marion57

    marion57 G&G Newbie

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    Tell me does it lock down tight when the bolt is forward?I seriously doubt you will have a problem with it .. That being said I must say there are always exceptions to every rule ,,I personally would shoot it
  19. K.H.

    K.H. G&G Newbie

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    Yes, it locks down tight when it is foreward.
  20. marion57

    marion57 G&G Newbie

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    SHOOT IT!
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