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Thread: ar 15 bolts ?

  1. #1
    Boolit Master
    nekshot's Avatar
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    ar 15 bolts ?

    What exactly is the difference in the bolts . I cannot find an answer to my question so it must be a widely known info that every one knows. You see a bolts for 223,300 and that is obvious. Then a bolt for the x39, and a bolt for the Grendel and one for the 6.8! Sorry, but I don't know.
    Look twice, shoot once.

  2. #2
    Boolit Buddy
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    The bolt face is bored to a diameter to accept the rim diameter of the brass.
    The only amendment the Democrats support is the 5th.

  3. #3
    Boolit Master
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    Quote Originally Posted by upnorthwis View Post
    The bolt face is bored to a diameter to accept the rim diameter of the brass.
    then I could buy one good bolt and only use different bolt heads according to cartridge in barrel chamber?
    Look twice, shoot once.

  4. #4
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    in theory, yes.
    you could have several bolts and only one bolt carrier.

    most people get a complete bolt carrier group (bolt+carrier+) with the upper assembly of their new cartridge choice.

    that way the correct bolt stays with the upper and makes for a quick swap.

    as for "good" bolt carrier, i prefer an m16 profile over an sp1 or improved ar-15 profile.
    just because, not for any noticeable difference.

    good luck
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  5. #5
    Boolit Grand Master Texas by God's Avatar
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    The Grendel and 7.62x39 are the same. But there's also .450 Bushmaster and .458 Socom. I agree about the dedicated bcgs.

  6. #6
    Boolit Master Moleman-'s Avatar
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    There are a couple companies (alexander arms for one) who don't always follow mil-spec for headspacing and the fancy rounded lug bolts and extensions that can't be mixed and matched with standard extensions and bolts. Both of these bolts are for .473" case heads, the rounded lugged one will handle 65K psi and the standard one only 40K psi safely.
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  7. #7
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    The bolt has to match the cartridge the fire arm is chambered for. Some cartridges have differed case designs. Diameter and depth of each bolt face are different. You can use the same bolt for parent case wild cats like a .223 for a .270 Wolverine ext. You have to be careful when getting a bolt and match them up. Due to head space, the barrel may require a different bolt for the same cartridge like the difference between a Grendel and Grendel 2 bolt. Bolt face depths are different on those two. Its been a while since i have had to get a bolt and don't remember all the technical spec, but that's it in a nutshell. Most distributors or manufactures have always listed what bolt is needed when something is different from the norm.
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  8. #8
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    Changing bolt only can damage gas rings, plus you can swap bolt carrier group easily and quickly.

  9. #9
    Boolit Master
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    I suggest a bolt /carrier for the .223,5.56.300 blk. I suggest another for the 6.5 and so forth so that your not taking them apart. They are NOT that expensive to have a bolt for every gun.

  10. #10
    Boolit Master
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    Quote Originally Posted by Moleman- View Post
    There are a couple companies (alexander arms for one) who don't always follow mil-spec for headspacing and the fancy rounded lug bolts and extensions that can't be mixed and matched with standard extensions and bolts. Both of these bolts are for .473" case heads, the rounded lugged one will handle 65K psi and the standard one only 40K psi safely.
    I assume the one on the right is the 65k. And that would be the one for the x39, correct? I appreciate all your input because my learning ability is slower than it used to be. I am fine with a bolt for each barrel especially when each bolt head lugs should be lapped to the barrel extension?
    Look twice, shoot once.

  11. #11
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    M-Tecs's Avatar
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    Quote Originally Posted by nekshot View Post
    I assume the one on the right is the 65k. And that would be the one for the x39, correct? I appreciate all your input because my learning ability is slower than it used to be. I am fine with a bolt for each barrel especially when each bolt head lugs should be lapped to the barrel extension?
    Quote Originally Posted by Moleman- View Post
    the rounded lugged one will handle 65K psi .
    That would be the one on the left.

  12. #12
    Boolit Master Moleman-'s Avatar
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    Nekshot, the bolt and extension on the left are the .473" high pressure ones. The extension on the right is a standard extension but you can mill or grind them into other types like center feed. The bolt on the right is a 450BM/458SOCOM.

  13. #13
    Boolit Master
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    wow, its good I am not playing poker!!
    Look twice, shoot once.

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Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check