Featured Semi Auto Does Not Work

Discussion in 'Gun Building, Modifications & Repairs' started by Rhyno34, Oct 4, 2017.

  1. Rhyno34

    Rhyno34 Member

    39
    4
    Hi all,
    I am building my first ground up aeg build and have had good luck until now. Everything on the aeg works except semi auto, it acts like it is on saftey. Full auto works like a charm so I am quite frustrated that I am having this problem. One of the issues I can see being is that the bearings on the gb (G&P) stick out too far and are pushing the selector plate outward. After messing around with it for a bit I have gotten it to shoot semi but it seems like the trigger trolley does not reset and the trigger goes slack (lonex trigger contacts and lonex trigger). Any help is appreciated and if you need anymore info or pictures just ask. Thanks again.
     
  2. -Spitfire-

    -Spitfire- Well-Known Member

    1,511
    173
    Martinsburg
    Pics would be lovely.

    202020202020
     
    BOA_SP3CT3R likes this.

  3. Rhyno34

    Rhyno34 Member

    39
    4
    Adding some pics of outside the gb showing the bearings and some on the inside
     

    Attached Files:

    -Spitfire- likes this.
  4. -Spitfire-

    -Spitfire- Well-Known Member

    1,511
    173
    Martinsburg
    So, when the gun is set to semi, you said it acts like it's in safety. I assume you mean that you can't pull the trigger back? Or can you pull it, and it just doesn't fire?
     
  5. Rhyno34

    Rhyno34 Member

    39
    4
    The trigger can not be pulled back when on semi correct. You think that the bowing of the selector plate is causing this?
     
  6. RockNRoll33

    RockNRoll33 Member Supporting Member

    188
    6
    Buford
    It could be one of two things. One, the bulging on the selector plate causes the selector switch little circle thing that puts it in the 3 modes is going under the plate on semi, but it can move it enough to put it in auto because the opposite side is not bulging. Two, your safety lever might be a little to long, try shaving it down a MM or two. I would be careful when doing that because you could ruin the lever by shaving off to much so just be careful. You can take as much as you want off but you can’t put it back on.
     
  7. Rhyno34

    Rhyno34 Member

    39
    4
    Alright thanks for the input I will try to shave down the safety lever a bit and if that doesn't work I will end up getting some 8mm bushings (has 8mm bearings now) and hopefully that should solve the problem. Thanks a lot.
     
  8. RockNRoll33

    RockNRoll33 Member Supporting Member

    188
    6
    Buford
    Oh and you could also shave a groove down the selector plate that’s the size and depth of the jetting out bushing.
     
    -Spitfire- likes this.
  9. Sitting_Duck

    Sitting_Duck Member

    302
    7
    OP - you really gotta post some pics
    a picture says a thousand words as they say if anybody is going to help

    take a couple of snaps, upload to imgur and paste link(s) or something

    what does the switch look like at the back - does it have prongs at rear
    copper plate on selector plate - are the prongs pushing out the selector plate ???
    [​IMG]

    The selector plate in semi position might just just be lifting Cut Off Lever
    though this could be due to plate being pushed out
    I have had to file very slightly the selector plate at COL point a whisker to ensure COL is down
    Though this has to be done with extreme care coz you may end up with a DMR selector plate

    So really you gotta try and help yourself & upload a pic or two....

    [​IMG]
     
  10. Rhyno34

    Rhyno34 Member

    39
    4
    here is a pic that I took a couple hours ago. My trigger contacts did not come with those prongs on the back.
     

    Attached Files:

  11. Rhyno34

    Rhyno34 Member

    39
    4
    Just tell me specifically what to take a picture of and I will take some.
     
  12. Sitting_Duck

    Sitting_Duck Member

    302
    7
    Well perhaps one showing the selector plate bulging out
    a pic showing the selector plate, bearings protruding
    The COL & selector plate in semi - sounds like COL is just slightly raised
    if thatbethe case you have a dead zone which is where the trigger won't pull
    due to the COL just not slipping under the trolley's lug
    something like this:
    [​IMG]
     
  13. -Spitfire-

    -Spitfire- Well-Known Member

    1,511
    173
    Martinsburg
    Duck, he already took pics. You really need to read all the comments. The issue is not the cutoff. It's the mechanical safety. This could be caused by a few things, and the only way to find out what specifically is causing it is to check fit and function of the gearbox, both in and out of the gearbox.

    OP, this could be caused by a few things. Do me a favor, put the gun in semi, double check that the issue is still present, then move the selector sightly towards the full auto position, repeatedly pulling the trigger until the point that the mechanical safety is pulled out of the way. Take a pic of where the safety is at that point. Basically, you're trying to find a point in between semi and full auto positions on the selector that allows use of semi auto.
     
    RockNRoll33 likes this.
  14. Rhyno34

    Rhyno34 Member

    39
    4
    Ok so putting the gb in the lower semi auto finally works to an extent. Yesterday I cut down the safety lever height wise and the trigger does pull and shoot in semi auto. Now the problem is the trigger does not completely reset (have to push the trigger forward to get to shoot again). So do you think this problem is with the trigger itself or the trolley?
     
  15. RockNRoll33

    RockNRoll33 Member Supporting Member

    188
    6
    Buford
    Sounds like you are missing the trigger spring.
     
    -Spitfire- likes this.
  16. Rhyno34

    Rhyno34 Member

    39
    4
    Trigger spring is in there I double checked
     
  17. -Spitfire-

    -Spitfire- Well-Known Member

    1,511
    173
    Martinsburg
    Does the mechanical safety still work when safe is selected?

    As for the trigger reset, remove the compression components from the gearbox, and looking down through the top, test functionality of the trigger assembly WITH THE GEARBOX SCREWED TOGETHER (that last bit's important).
     
    RockNRoll33 likes this.
  18. Rhyno34

    Rhyno34 Member

    39
    4
    Yeah safety still works, only semi is doing this
     
    -Spitfire- likes this.
  19. -Spitfire-

    -Spitfire- Well-Known Member

    1,511
    173
    Martinsburg
    Added a bit more to my previous post.
     
  20. Rhyno34

    Rhyno34 Member

    39
    4
    took out the compression parts and put the gb back into the lower and the trigger does not have a problem, no sticking no locking. Could the tappet plate be interfering with the trigger possibly?