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Thread: Crush washer or lock nut?

  1. #11
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    Quote Originally Posted by Hmac View Post
    Huh? What muzzle devices, what do shims have to do with tight exit hole diameters?
    The same thing using shims has to do with MDs designed to mount cans.

  2. #12
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    Quote Originally Posted by Auto-X Fil View Post
    I prefer shims. If you do a lot of devices, having this kit around is the best way - you can just use a single shim to get the correct torque and clocking.

    http://precisionarmament.com/product...washer-system/
    +1

    All I use

  3. #13
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    Quote Originally Posted by Hmac View Post
    To tighten a crush washer, it only needs 90 degrees of rotation to get sufficient torque to hold the device in place. To use it properly on a muzzle device requires tighten-loosen-tighten-loosen-tighten 90-180 degrees to the proper timing of the device. Overtightening a crush washer would mean that it's not being used the way it's designed. You never bottom the threads. A portion of it has to be "un-crushed".
    I have always used crush washers with this same method, and never had an issue getting the timing down proper.

    I will, however, be trying the shim kit on the next go around.

  4. #14
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    Learning a lot. Thanks all.

  5. #15
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    Quote Originally Posted by HeruMew View Post
    I have always used crush washers with this same method, and never had an issue getting the timing down proper.

    I will, however, be trying the shim kit on the next go around.
    I see people here on M4C talk about using shims with a crush washer to get it timed right. I conclude that many people don't understand how to use a crush washer.

  6. #16
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    Quote Originally Posted by Hmac View Post
    I see people here on M4C talk about using shims with a crush washer to get it timed right. I conclude that many people don't understand how to use a crush washer.
    That's funny right there.

  7. #17
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    Crush washers and lock nuts are not things to use when alignment counts. Precise shims and machining are for best alignment in all planes. A precise lock nut adds to a tolerance stack, that's not avoidable.
    If the MD does not require that level of orientation, then the option may work out. Many others are better suited with precise shims and lower end torque values for their application.

  8. #18
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    I'll agree that shims might be important if concentricity is important. If it's just about timing, then crush washer is the ideal mechanism for attaching a muzzle device and shims do nothing but add an unnecessary level of futziness.

  9. #19
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    You can choose to do so, just depends on the alignment requirements for the muzzle devices. There is no set means, using a means that fits the user properly should be a goal over one that does not.

  10. #20
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    Quote Originally Posted by Hmac View Post
    To tighten a crush washer, it only needs 90 degrees of rotation to get sufficient torque to hold the device in place. To use it properly on a muzzle device requires tighten-loosen-tighten-loosen-tighten 90-180 degrees to the proper timing of the device. Overtightening a crush washer would mean that it's not being used the way it's designed. You never bottom the threads. A portion of it has to be "un-crushed".
    The ID of the crush washer grows smaller and its OD grows larger as it's being crushed. I've had a crush washer get stuck on the threads a couple of times when removing a muzzle device, even though the washer was not completely crushed. One was a factory installation.

    Crush washers are a pain. Go a little past when trying to align a muzzle device and you have to start over again with a fresh washer- or go all the way around again. Too much work. Shims are easier. I find shims ate much more positive and repeatable than crush washers or peel shims. If the muzzle device clocks early, use a thinner shim. If it clocks late, add a shim or use a thicker shim
    Last edited by MistWolf; 04-13-16 at 02:19.
    INSIDE PLAN OF BOX
    1. ROAD-RUNNER LIFTS GLASS OF WATER- PULLING UP MATCH
    2. MATCH SCRATCHES ON MATCH-BOX
    3. MATCH LIGHTS FUSE TO TNT
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    5. HA-HA!!

    -WILE E. COYOTE, AUTHOR OF "EVERYTHING I NEEDED TO KNOW IN LIFE, I LEARNED FROM GOLDBERG & MURPHY"

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