Hopefully helpful Walther LGU trigger mod.

Discussion in 'Tips, tricks and tutorials' started by sunbeam, Apr 13, 2018.

  1. sunbeam

    sunbeam Member

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    Hi Guys,

    On another forum I posted this, but I thought you guys on this forum would also like to know, just spreading the love :)

    All the Walther LGU trigger mods are done and I can report that the trigger is now PERFECT for me.

    I think the pictures show as much as you need to see, and it can all be done with hand tools (apart from the trigger blade bush)

    Basically, all I have done is to reposition the second stage adjuster closer to the first stage screw. I stole that idea from another poster somewhere.

    My engineering solution to moving the second stage screw over was to make the little brass 'T' piece and remove the metal on the trigger casting. It has two 3mm holes and one M3 threaded hole. Note the corner taken off so the safety can still engage. It works perfectly and has an awesome second stage, almost PCP good !!

    I found that cutting the spring and holder down to 9mm overall enables a nice light trigger, but the trigger sear can reengage when the trigger is let off the first stage and the grub screw is not hanging out! Note that I have removed the very small spring in the trigger as it's not needed.

    Set up the screws as perfectly as you can with the side off and measure the heights of the screws with a digital gauge. Note you'll need to push the three pins down with your fingers to simulate the side that is off. Add thread Lock to the second stage screw and put it back quickly and check it's height, adjust as needed while the thread lock is wet. Once the side is screwed back on, the trigger second stage maybe a little off as the pivots will be in a slightly different place. All the adjustment can now be done on the first stage screw, as it is only a very fine turn needed. When I put mine back together I had no second stage, but I only needed half a turn on the first stage to get the second stage back. Now I have a nice light but positive first, and only need slight pressure to fire the second. The trigger doesn't move on the second, you just fire, I have 4mm of movement on the first stage :)

    Trigger has lots of side play, drill out the pivot hole to 3.5mm.
    Turn up a tube, 2.9mm ID, tight fitting 3.5mm OD.
    Push the tube into the trigger blade hole (tight fit!) then CAREFULLY ream out the ID until it is a perfect fit on the original 3mm shaft.
    No more play :)
     

    Attached Files:

    Joha likes this.
  2. Dale

    Dale Active Member

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    Nice, ingenious solution!

    I am happy to see my suggestion being stolen and being proved to be correct about the wasted leverage in this design!

    Now if Rowan Engineering will take note they can elevate their product to another level.
     
  3. hmangphilly

    hmangphilly The Doctor

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    no top hat inside the bottom coil spring on the one ive got here
     
  4. poth

    poth Whafta old Gits world champion

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    Simple and effective well done any measurements for the brass Insert
     
  5. sunbeam

    sunbeam Member

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    To be honest, I didn't make the brass with any measurements, just did it by eye ball.
    As long as the brass is no bigger than the trigger casting and the top is about 2mm think, none of the measurements matter.
    All you are doing is introducing extra metal inbetween the cast trigger posts.
    Just make sure the new m3 grub screw misses the head of the m3 bolt in the old second stage thread.
    There is nothing to 'rocket science' about it really.
    The depth of the middle bit can be anything deep enough to get a usable thread into, about 7mm'ish will do.

    I don't know why your gun didn't have the top hat?
    You could always have one spun up.
    I dare say it's not too important as the grub screw has a taper and the spring sits in a hole.
    The top hat just makes everything seat better.
    Also the top hat will stop the spring getting pinched in the threads by the grub screw.
    You could even make that simple part by putting a brass bar in a drill and file the brass into shape with the drill on fully fast. It's a bit harsh, but it'll work ;-)
     
    Last edited: Apr 13, 2018
  6. Adam

    Adam Active Member

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    The top hat as it comes from factory does limit how low the trigger weight will go, so some folks turn it and spring upside down, or junk the top hat.
     
  7. sunbeam

    sunbeam Member

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    I found that if you cut the spring down with a good pair of side cutters so that the spring and top hat measure 9mm, a really nice trigger weight can be had.
     
  8. Andy G

    Andy G New Member

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    Hi, I made a brass modification and the trigger is so much better for it. I rounded and highly polished the two screw ends and also polished the sear face they slide on to a mirror finish. I also shortened the trigger weight spring down to approx. 9mm long including the top hat.
     

    Attached Files:

  9. garym

    garym Active Member

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    I like and appreciate all these mods, at the moment I want to work on my LGU trigger. No, I shall re word that. Rip the bloody thing out. That long 1st stage irritates me.

    Having looked at all the options. No hand tools or brass available. I am in the backwaters of Bulgaria :eek:.

    That leaves me with a option of a Rowan Engineering or Tony Leach trigger replacement. ( Too much free time today, lots of research! ) Choices.
    Rowan, great service in the past. 53 quid is a bit steep for a trigger though.:(
    Tony Leach, the only contact info I can find is on facebook. I am a old git. I am not a facebook user.
    Anyone any idea of the cost of a LGU trigger from Tony Leach?
    Thanks Gary
     
  10. pelletcaster

    pelletcaster New Member

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    garym likes this.
  11. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    I believe a standard TX200 trigger blade will also fit with a small amount of filing.
    The Bruno blade that Tony sells is about £35 + post
     
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  12. garym

    garym Active Member

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    Thanks mate, and Happy New Year.
    the trigger on the German site is no different to what I have now. I will save the link though.:)
    I have already ordered the brass T piece, I just fancy trying a different trigger design to make a comparison. These LGU's are as addictive as the CZ200's.
    Thanks and regards Gary
     
  13. garym

    garym Active Member

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    Great info. Thanks Brian.
     
  14. Adam

    Adam Active Member

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    You can dial out the excessive first stage travel on the first screw by winding it in several turns. This reduces the total travel between rest and firing. Doing so will lose the second stage, which you then get back by also winding that screw in until it just touches the sear before the break point.
     
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  15. garym

    garym Active Member

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    Tomorrow I will experiment. Thanks Adam.
     
  16. vangard

    vangard Member

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    I have just set the trigger on my LGV master pro, and I found it easy to do with the trigger box open.
    It means dismantling the gun, but you get a better idea how it works that way. The fine tuning can be done when it is set and put back in the stock.
     
    garym likes this.
  17. MickyFinn

    MickyFinn I❤HFT

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  18. garym

    garym Active Member

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    That is a definate improvement, Thanks Adam:)

    But I love to tinker,;). The trials continue.
     
  19. garym

    garym Active Member

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    Thanks vanguard, I done the same today. All went well until my English Bull terrier started to investigate. Bits everywhere. :(
    Magnets and google pics helped to find the bits, then reassemble. all is ok now.
     
  20. garym

    garym Active Member

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