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  1. #21
    XCR Guru navalbeaver's Avatar
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    Ooohhhhh.... Sounds like some dial swapping is in order.... Keep us posted.

  2. #22
    XCR Guru Sean K.'s Avatar
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    Quote Originally Posted by navalbeaver View Post
    Ooohhhhh.... Sounds like some dial swapping is in order.... Keep us posted.
    Will do. If it works, I'll probably be in touch to see if you can't find me a dial with bigger holes. Otherwise, I guess I can contact RA and see how that goes....LOL. That should be interesting.
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  3. #23
    XCR Guru navalbeaver's Avatar
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    I don't think I've got anything bigger than the x39 dial. The 300 might be a little more bored out.

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  5. #24
    XCR Guru Sean K.'s Avatar
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    Quote Originally Posted by navalbeaver View Post
    I don't think I've got anything bigger than the x39 dial. The 300 might be a little more bored out.
    No biggie. I'm going to have to contact RA once I get more accurate measurements. I don't have Deltronics pins here, but I have them at work. I've got a non-cal'd set of gauge pins.

    I need to know what size they normally port the bbls in this length/gas config. I'll make a new post below for info purposes.
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  6. #25
    XCR Guru Sean K.'s Avatar
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    Data Points:

    12" .308 1:7 twist bbl with mini length Type 3 gas system.

    Below are numbers from a factory supplied bbl and type 3 gas system. Did RA supply these parts with correctly specified holes? Unknown.

    12" bbl port size is .089".
    .308 gas block port size is .125".
    .308 dial position 0= no hole
    Position 1 is less than .040"
    2 is also less than .040" (I don't have gauge pins that small)
    3 is between .046 and .051"
    4 is .052"
    5 is .059"
    6 is .063"
    7 is .067"

    Gas dial on the 7.62x39 with 9.5" bbl and mini length gas system
    Position 0 has no hole
    1 < .040"
    2 = .052"
    3 = .059"
    4 = .073"
    5 = .081"
    6 = .093"
    7 = .125"

    The bbl port in the 12" .308 seems awfully small....but since you have the volume of powder in a .308 case, the pressure may be matched to that smaller port size. Obviously, it's easiest/smartest to just put in the dial with the bigger ports and run it and see. I guess I could have some of the "nerds" at my work do a CFD analysis of it...but then they have to build a model. It'd be much easier if RA would just tell me when I ask. Last time I did, that went over like a fart in church though, so I doubt I'll get any traction there.

    I'll keep you guys in the loop so that if anyone else runs into this, there's at least a starting point for trouble shooting.

    ***ETA*** Numbers amended where applicable. Couldn't get a hold of our small set of pins as they were being used elsewhere today. ****
    Last edited by Sean K.; 07-08-2018 at 06:54 PM.
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  7. #26
    XCR Guru fmunk's Avatar
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    Quote Originally Posted by Sean K. View Post
    Permanent degradation....but at least I can see at all. I'm grateful for that. My distance vision in that eye now is pretty poor whereas before it was 20/20 or better. Up close is fine at this point....but it's just not "clear". Things are a bit "fuzzy" if you will.

    Thanks for asking.

    Not your dominant eye I hope? Does it make the wife look better? Just kidding.
    Fool-proofing serves only one purpose: identify bigger fools.

  8. #27
    XCR Guru Sean K.'s Avatar
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    Quote Originally Posted by fmunk View Post
    Not your dominant eye I hope? Does it make the wife look better? Just kidding.
    Nope...my luck continues. Dominant eye. Wife looks just fine regardless...she's even more beautiful on the inside and that just seems to get better with time.
    TexasChris, Merlin and Carpenter like this.
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  9. #28
    XCR Guru fmunk's Avatar
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    Oh man, sucks that it's your dominant eye. Glasses help at all or is it nerve damage? With time I think your brain will adjust to make the other one the dominant.
    Fool-proofing serves only one purpose: identify bigger fools.

  10. #29
    XCR Guru Sean K.'s Avatar
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    Quote Originally Posted by fmunk View Post
    Oh man, sucks that it's your dominant eye. Glasses help at all or is it nerve damage? With time I think your brain will adjust to make the other one the dominant.
    Been a year now....no change in dominance. Glasses help with distance, but not close up. Driving really sucks now, especially at night.
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

  11. #30
    XCR Guru Sean K.'s Avatar
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    So good news....X39 dial works 100% with the 12" bbl on the .308 on setting 7. On setting 6 I had a failure to extract/eject. Same with 5 and 4....a few here and there. Those may just be due to needing more break in. Recoil is still fine.... Ran 75 rounds through it. Man, this sucker gets HOT!!

    Next step is to contact RA after the holiday and ask to confirm bbl port size and dial sizes.
    Merlin and TexasChris like this.
    "Necessity is the plea for every infringement of human liberty. It is the argument of tyrants; the creed of slaves."-William Pitt the Younger

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