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headspace ?

SilentRageSilentRage Member Posts: 103 ✭✭
edited November 2013 in Ask the Experts
Ive read alot about the need to check headspace on mosin nagants, but, if the bolt is able to extract the round, wouldn't that mean the bolt face is against the rim and therefore headspace is good? There really isn't much tolerance between the extractor lip and bolt face
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Comments

  • tsr1965tsr1965 Member Posts: 8,682 ✭✭
    edited November -1
    SilentRage,

    NO. The headspace is measured from the bolt face to which ever feature the cartridge design uses to head space. Rimmed cartridges use the back side of the rim, Belted cases use the back side of the Belt, Rimless cases, use the fulcrum of the shoulder, while straight sided, rimless pistol rounds, use the case mouth.

    Consider the extractors to be spring loaded, and they automatically adjust to numerous indifferences, during chambering a round. Some controlled round feed(read as Mauser Claw type extractors), pick up the cartridge from the magazine, under the extractor, to prevent dropping a round. In other words, just because the case head, is held back against the bolt face, doesn't mean you do not have a headspace issue. You can still have enough wiggle room, to cause a problem.

    Most full service gunsmith's/gunshop's, will have a 7.62x54 headspace gauge. I suggest, that you take it to one.

    Best
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  • SilentRageSilentRage Member Posts: 103 ✭✭
    edited November -1
    I have thought of buying some headspace gauges and checking them myself(I have 13 mosins) It would probably be worth the $50+ just to be safe.
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  • Hawk CarseHawk Carse Member Posts: 4,381 ✭✭✭
    edited November -1
    I always wonder what one does when he finds his cheap surplus rifle to have incorrect headspace.
    Is he set up to fix it himself?
    Is he going to pay a gunsmith more to adjust it than the original price of the surplus?
    Is he going to motor on with surplus ammunition, not caring if it does anything short of casehead separation?
    Is he going to adjust his loading dies to accommodate a nonstandard headspace?
    Is he going to sell his problem to somebody else?
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  • charliemeyer007charliemeyer007 Member Posts: 6,572 ✭✭✭
    edited November -1
    Dad had a Santa Barbra Mauser in 30-06 that worked fine with neck sizing only. We had an Enfield in 30-06 that had to have the barrel set back one thread to fix the issue. The second best shooter I ever had was a Springfield that was punched out to 300 Gibbs, I suspect was long in headspace originally.

    My Winchester 94 AE in 44 Mag had a few issues. It was Christmas gift from the company. The box was wrong but the gun looked new. I just used it as a loner gun/truck rifle. Anyway, the right cartridge was crack threw the screw hole and jammed the action, that resulted in a broken lifter tip. I made and installed a bushing in the hole to return it to the original screw. Then it developed headspace issues reveled by stinging your hand in the finger lever. I used a wire feed welder to add some metal to the end of the bolt and filed it to fit. I made an extension for the lifter but haven't welded it in yet. The rifle will function without the extension if you cycle the action rapidly but I'll fix it someday.

    Being a reloader I pick up brass. I have seen a fare number of cases that had bulges and signs of excessive headspace. I suspect the shooter's had no clue their firearm had issues.
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  • SilentRageSilentRage Member Posts: 103 ✭✭
    edited November -1
    I always wonder what one does when he wakes up in the morning? Does he go to the bathroom then brush his teeth? Is he going to have a smoke before or after breakfast? Is he going to take a shower and get ready for work? Does he say to himself..."I'm going to read the forums first and help this guy with his headspace question? "

    Inappropriate and unacceptable language. Read the Posting guidelines
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  • SwanKongSwanKong Member Posts: 989 ✭✭✭✭
    edited November -1
    quote:Most full service gunsmith's/gunshop's, will have a 7.62x54 headspace gauge. I suggest, that you take it to one.


    tsr1965 gave you good advise...
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  • TRAP55TRAP55 Member Posts: 8,292 ✭✭✭
    edited November -1
    Myself and another forum member here, checked the headspace on a dozen or so Mosin model variants that we had between us. Receiver production ranged from 1896 to 1955.
    All were within spec.
    Then we checked each bolt, in each different rifle.
    Still all in spec.
    Pretty damned impressive for a "cheap" military surplus rifle. A couple were war time production, being manufactured and assembled while in full retreat from the Germans, with the factories in tow.
    Try that same headspace test on some Enfields, Springfields, or Mausers, and see what your results are.[;)]
    SilentRage, FYI...You can change any piece of the bolt assembly, with the exception of the bolt head, and the headspace will remain the same.
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  • Don McManusDon McManus Member Posts: 23,681 ✭✭✭✭
    edited November -1
    Brownell's has the Clymer Gauge sets for $ 70.00.

    Probably is worth the money given 17 rifles.

    (about half-way down the page)

    http://www.brownells.com/gunsmith-tools-supplies/measuring-tools/headspace-gauges/go-no-go-gauge-sets-prod26876.aspx

    I use them before every gunshow purchase. Just seems to make sense.
    Freedom and a submissive populace cannot co-exist.

    Brad Steele
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