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Thread: Bolt Gap/Ground Bolt Head

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    Veteran FERRUM Ab VERITAS's Avatar
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    Bolt Gap/Ground Bolt Head

    My CAI cetme has a bolt gap of 0.015, but it seems our dear, intellgent friends at Century ground my bolt head, so i'm going to order a new bolthead, but What is this going to do to my bolt gap? and how do I FIX IT?

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    your bolt gap measurement will decrease with a new bolt head, since your old gap of .015 was a false reading

    if your new gap is still in spec, then you really dont need to do anything. if your new gap is low, you may need to replace your rollers with +4's

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    Veteran JayGeeWentWorth's Avatar
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    A new locking piece may also help if your gap is too low. If getting the larger rollers and new locking piece still doesn't get you in spec, then you may have to repress your barrel.

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    Ol'30 Grit jfowl31's Avatar
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    a thought in addition to what Hunter said...

    A new bolt head will not ALWAYS shrink bolt gap, though it is most common for it to. If the old bolt head was worn badly, and that is what caused the low BG and caused CAI to grind it, then a new bolt head may actually get everything back into spec.

    best bet is to start with a NEW bolt head, then if your out of spec, NEW +4s and a NEW locking piece and see where that gets you.
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    Veteran texlurch's Avatar
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    Quote Originally Posted by FERRUM Ab VERITAS View Post
    What is this going to do to my bolt gap?
    Measure your bolts length.

    Subtract from 1.835"

    Subtract the result from the gap you have now, and that will tell you the actual bolt gap.

    your gap now is .015
    say your bolt is 1.825, = -.010
    that means your actual gap would be .005. (.015 - .010)

    This is just for example, do the actual measuring and calculating on yours.

    You might also want to measure your roller diameter, to verify what size you already have, before you jump and order a set of +4. CIA has been known to make their own oversize rollers trying to "fix" things.

    In short, measure and check to see what you have, before you just start throwing parts at it.
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    Measure your bolt gap; subtract your IQ; stand on your head; run around the block; check your blood pressure--this will give you your TRUE bolt gap.

    Nature Boy

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    Veteran Buzz's Avatar
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    Quote Originally Posted by Nature Boy View Post
    Measure your bolt gap; subtract your IQ; stand on your head; run around the block; check your blood pressure--this will give you your TRUE bolt gap.

    Nature Boy
    And then have a neighbor test fire the darned thing.

    Buzz

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    Veteran Blaster's Avatar
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    Quote Originally Posted by Buzz View Post
    And then have a neighbor test fire the darned thing.

    Buzz
    Then ya better make sure that neighbor is NOT a lawyer.

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    Veteran Buzz's Avatar
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    Quote Originally Posted by Blaster View Post
    Then ya better make sure that neighbor is NOT a lawyer.
    Good advice! And that is coming from a lawyer

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