Green Mountain barrel Blank

Discussion in 'Gun Project Questions & Gunsmithing' started by strobes, May 20, 2020.

  1. strobes

    strobes

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    Hi, I'm considering this7MBLANK-01 19.25" x 1.062" 7mm barrel Blank 1:9.5 twist,
    It is unturned. What diameter I should expected after turning on centers? Will I get about 0.98 on chamber end to thread an action?
     
  2. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Thats not even big enough to thread for a mainstream action if you turn it down
     
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  3. hoz53

    hoz53 Gold $$ Contributor

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    were you planning on making an Ar-15 or AR-10 barrel out of that?
     
    Last edited: May 21, 2020
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  4. Ggmac

    Ggmac

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    It's a crap shoot . It all depends on the barrel being concentric to the bore . I've had green mtn barrels that were centered and others that were .060 off . If you buy one of the turned blanks , they are spot on . I've had good luck with green mountain barrels but don't Borescope it till you shoot it !
     
  5. strobes

    strobes

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    yes, that is what I was thinking, if it's concentric.
    I'll cal and ask what specification is to know expected tolerances.

    hoz53 - yes something like that.
     
  6. tobnpr

    tobnpr

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    Good luck on specs with them...
    I called once inquiring about the tolerances on their bore/groove dimensions- and was told .003 :eek:

    I've only ever used their "raw gunsmith" blanks as bull barrels on Mosin-Nagant receivers and they've all shot under a minute.
     
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  7. Ggmac

    Ggmac

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    Good luck , but they do have 1.25 blanks occasionally. What action do you want it for . A small ring mauser or a mossberg atr will be easy a savage or rem 700 or 783 probably will not work .
     
  8. hoz53

    hoz53 Gold $$ Contributor

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    sounds like he wants it for an AR 15 Ggmac -- thats why he wants it .998
     
  9. hoz53

    hoz53 Gold $$ Contributor

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    Ha ha. yeah I got a couple of the gunsmiths blanks from them to practice when i started. They did shoot good for the money but Id say their groove on mine mite not be more than .003. deep---So its +/- groove or nogroove:confused:o_O:eek:
     
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  10. msalm

    msalm

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    I’ve used quite a few of them for lesser expensive projects. After contouring I cast a lead lap and lap the bore. Generally they clean up extremely well as their ream before rifling is generally very good. They have always easily shot sub MOA. AR barrels and some bolt rifles. They usually are a bit oversized (bore) but that doesn’t seem to stop them from shooting very well. With the extra work of contouring and lapping it’s only worth it if you don’t value your time much!
     
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  11. strobes

    strobes

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    Plan is to do remage design for AR-10 in 7mm-08
    I googled AR 15 Ggmac - no references - what is it?
     
    Last edited: May 24, 2020
  12. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Gmac is a guys name. Put a comma between ar15 and gmac and youll see what he meant
     
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