Rifle Scopes Checking scope ring screw torque

Nik H

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  • Jan 22, 2014
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    Small town New England
    Went to a local impromptu tourney today and halfway through found that my low scores were the result of my scope rings coming loose. Using a Spuhr 4016 mount on an AR-10 holding a Khales 6-24.

    They were properly torqued a long time ago and I never thought to periodically check them. So the questions I have for the group are:
    1. Do you guys use blue loctite as a rule when installing a scope?
    2. How often do you check the torque?
    Thanks in advance
     
    I always use Loc-Tite (blue) on not only the ring caps but the base screws as well - yeah, ask me why.. ;) (same thing, was spot on 1st half of a day, second half I thought my optic was losing zero, wasted much ammo to find out the base had started to loosen up).

    No 'regular' schedule on checking/re-checking torque but usually before/after a 'long' shooting day (e.g. 100+ rounds), otherwise at least every few months.

    For brand new optics, I'll cheat slightly in that I'll Loctite the base screws once I'm sure there, torque down cap screws, shoot through all positions, make any minor adjustments fore/aft if need be, sanity check, then usually back out a screw at a time to Loctite, then final sanity check. Haven't had an optic shift/move on me to date doing this, although someone else may have a better idea..
     
    Last edited:
    Thanks all...

    I bought some blue on the way home at ACE and re-torqued everything when I got home.

    This was actually a good thing as I have a new NF scope coming for my AT. All of my rifles, therefore, get an optic upgrade. Since all optics need to be re-mounted onto new rifles, this is the prefect time to loctite. I also will start checking things, at least, before every important event.

    One thing that I don't get. This scope/mount was on an AR10 and I moved it to my AR15 yesterday. I didn't touch the rings. I literally moved the mount/scope from one Larue to another. I cant believe that would contribute to this happening. I did a quick check on my primary rifle, an AI AT with NF Ultralight rings that has had significantly higher rounds through it than the AR10. Actual torque settings on the rings and bases on my AI were really good.

    Is the fact that this was a semi (AR10) a contributing factor. Do semi autos require more regular checks?
     
    One thing that I don't get. This scope/mount was on an AR10 and I moved it to my AR15 yesterday. I didn't touch the rings. I literally moved the mount/scope from one Larue to another. I cant believe that would contribute to this happening.
    When you say "scope rings came loose", I assume you mean the screws that hold the halves of the rings together came loose. If that's the case just moving the scope/mount combo from one rifle to another had nothing to do with the ring caps loosening.


    Is the fact that this was a semi (AR10) a contributing factor. Do semi autos require more regular checks?
    I think so. Bolted joints loosen primarily from two phenomena: joint relaxation and vibration. Semi autos obviously vibrate more than other types of firearms due to their design, and AR10s have a pretty massive bolt carrier assembly slapping back and forth on every shot.

     
    When you say "scope rings came loose", I assume you mean the screws that hold the halves of the rings together came loose. If that's the case just moving the scope/mount combo from one rifle to another had nothing to do with the ring caps loosening.

    This is the case. Screws were very loose.

    I think so. Bolted joints loosen primarily from two phenomena: joint relaxation and vibration. Semi autos obviously vibrate more than other types of firearms due to their design, and AR10s have a pretty massive bolt carrier assembly slapping back and forth on every shot.

    Thanks Pirate. That is what I thought. I have put blue loctite in place and re-torqued the screws.