AR15 Gas Block rotated a few degrees off center. Problem, or not?

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  • 2AOK

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    I've built rifles from parts kits, but have no experience with AR15s. A friend showed me his new, unfired budget AR and I noticed that the gas block appears rotated a few degrees.

    There are two set screws at the bottom of the gas block, unstaked. I'm guessing the barrel was dimpled to accept those screws. They're aligned with one another, and should be aligned with the handguard M-LOK rail below, but they're not. So it's easy to see the block is rotated in relation to the barrel circumference.

    I'm used to piston-driven gas systems, where a canted gas block would be problematic. But with AR15 direct impingment, I don't know. My concern is this: A hole was drilled in the top of the barrel for the gas to exit, BUT...if the hole in the gas block does not align with that hole through the barrel's upper wall, the flow of gas will be impeded leading to (perhaps) failure to cycle.

    The rifle's unfired, and I'm hoping this is not going to be a problem. I found THIS LINK wherein some AR15 owner/builders don't appear too worried about it. Any advice from INGO members would be much appreciated.
     

    patience0830

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    "A few degrees" is fairly vague. If the hole isn't under the port, it won't run right. If it's partially under the port, it may run fine with hotter loads and jam with lower velocity stuff. If it won't run, start the troubleshooting at the gas block.
     

    bwframe

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    How much do minor signs of a leaky gas block need to be addressed? I have run into more than one rifle showing minor signs of gas leakage, (especially obvious on stainless barrels,) that the guns seemed to run fine?
     
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    2AOK

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    "A few degrees" is fairly vague. If the hole isn't under the port, it won't run right. If it's partially under the port, it may run fine with hotter loads and jam with lower velocity stuff. If it won't run, start the troubleshooting at the gas block.
    My thinking exactly.

    Can only estimate how many degrees the GB is rotated. I'm guessing 3 or 4ish. Rifle has a lifetime warranty, but removing the free-float handguard (to pull the gas block) voids the warranty.

    Catch-22
     

    2AOK

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    How much do minor signs of a leaky gas block need to be addressed? I have run into more than one rifle showing minor signs, (especially obvious on stainless barrels,) that the guns seemed to run fine?
    I don't know the sequence of events in installing/assembling gas block to barrel. I'm assuming the barrel was pre-drilled TDC and then the gas block was mounted slightly rotated. Whether that results in a minor or a MAJOR impediment is determined by how much those two passageways are out of alignment. Hopefully very little.

    The lack of a gas piston probably means one can get away with a sloppier assembly in this respect. Let's hope so.
     

    NyleRN

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    To me it would be much more of a hassle to send it back for a slightly misaligned gas block. I personally wouldn't care about a warranty. But I understand if you don't know how to work on it.
     

    dieselrealtor

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    Fire it with some lower velocity .223 ammo, if it functions & ejects properly I wouldn't worry about it. It is possible the gb may have a much larger port than the barrel making alignment a non issue.
     

    Goodcat

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    The GB port will be significantly larger than the barrel port. I would personally fix the issue. But if you don’t want to, and it’s ejecting 4:00 ish, you have no real issue.
     

    T-DOGG

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    Every gas block I have ever installed has a much larger gas port than the barrel does, so there is some room to compensate for a slight misalignment. Shoot the gun, it should be fine.

    Also, I don't recall ever seeing any manufacturer staking gas block set screws either. I dimple the barrel with a jig and loctite mine. YMMV.
     

    2AOK

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    Well...thank you, guys, for your helpful suggestions/insights.

    Based on your comments, an email inquiry has been sent to the manufacturer outlining the issue. Hopefully they'll assist in sorting the rifle out. I'll post here with further developments.

    Happy Thanksgiving
     

    Goodcat

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    Well...thank you, guys, for your helpful suggestions/insights.

    Based on your comments, an email inquiry has been sent to the manufacturer outlining the issue. Hopefully they'll assist in sorting the rifle out. I'll post here with further developments.

    Happy Thanksgiving
    Let’s us know. Let me guess. Bear Creek Arms?
     

    2AOK

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    Let’s us know. Let me guess. Bear Creek Arms?
    I like the mfr. They've had their problems but are making great strides now. So, though I understand your curiosity, I'll hold off on identifying them. If they come through with flying colors, maybe THEN I'll mention their identity.

    You're a Goodcat, so I know you understand. :D
     
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