puzzled by head spacing
Page 1 of 2 1 2 LastLast
Results 1 to 15 of 16
  1. #1
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times

    Puzzled by head spacing on a MAK-90

    My MAK-90 will close on a GO gauge but not on a No-GO gauge when I test it with just the bolt, no carrier.
    However, if I place the bolt into the carrier and check the NO-GO gauge again, the carrier will come to rest up against the trunnion.

    Does that mean the bolt is also closing? I'm not putting a lot of pressure on the carrier either so I'm confused as to what's going on
    with the bolt when the carrier is thrown into the mix.

    The bolt has virtually no wear on it and upon close inspection I see no burrs or unevenness of the lugs

    The trunnion likewise appears to be in perfect shape.

    Please let me know if you guys want pics.

    Any help is appreciated!
    Last edited by natlmatch; 06-30-2020 at 08:58 PM.

  2. #2
    Senior Member

    Member #
    20323
    Join Date
    May 2011
    Posts
    4,298
    Liked
    1149 times
    take the bolt and pull it from the carrier. Lock it into the lugs and tell me how much it pushes forward and back. It should just a literal half a cunt hair.

    Sounds like your fine either way.
    WTB:

    Russian Type 1 or 2 parts/kit

  3. #3
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times
    Quote Originally Posted by evolixsurf View Post
    take the bolt and pull it from the carrier. Lock it into the lugs and tell me how much it pushes forward and back. It should just a literal half a cunt hair.

    Sounds like your fine either way.
    Yes Sir, that's exactly what it does, it barely moves when locked up with no gauge.

  4. Remove Advertisements
    TheAKForum.net
    Advertisements
     

  5. #4
    Super Moderator
    Supporting Member

    Member #
    21201
    Join Date
    Feb 2012
    Posts
    13,722
    Liked
    9185 times
    Who's gauges?

  6. #5
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times
    bolt-fully-closes-on-no-go.png
    carrier closes fully to Trunnion with No-Go gauge inserted

    Bolt with No-Go gauge using light finger pressure.
    field-guage-with-light-finger-pressure.png

  7. #6
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times
    Last edited by natlmatch; 07-01-2020 at 04:00 PM.

  8. #7
    Super Moderator
    Supporting Member

    Member #
    21201
    Join Date
    Feb 2012
    Posts
    13,722
    Liked
    9185 times
    CIP or SAMMI spec gauges? There is a big difference between the two.

  9. #8
    Senior Member

    Member #
    21581
    Join Date
    Jun 2012
    Location
    Tipping cows in fields Elysian
    Posts
    1,256
    Liked
    331 times
    90E36625-C01B-4CCF-848B-70DE0CC5FF7F.jpeg
    This what the red arrow is pointing to should cam over and touch the front trunnion on the go gauge to be at full lockup. It should not cam over and touch on the no go you should have around .100 thou gap or more. And in the carrier it will be more like a .25 inch gap from closing if your headspace is good.

    Are you just pushing forward on the bolt with light finger pressure or actually pushing froward and caming the bolt clockwise to make it cam over and lock. You have to make the bolt try to cam over when its not in the carrier. Just pushing forward isnt going to tell you anything.
    I grab the top lug what your finger is touching in the last picture grab that with your index finger and pull it clockwise to cam over.
    if its closing all the way on the no go in the carrier shes alittle loose.
    Last edited by NXCHESTER; 07-01-2020 at 06:44 PM.

  10. #9
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times
    Quote Originally Posted by 22many View Post
    CIP or SAMMI spec gauges? There is a big difference between the two.
    22,
    Looks to be SAMMI

    https://mansonreamers.files.wordpres...tolerances.pdf
    Last edited by natlmatch; 07-01-2020 at 07:28 PM.

  11. #10
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times
    Quote Originally Posted by NXCHESTER View Post
    Are you just pushing forward on the bolt with light finger pressure or actually pushing froward and caming the bolt clockwise to make it cam over and lock. You have to make the bolt try to cam over when its not in the carrier. Just pushing forward isnt going to tell you anything.
    I grab the top lug what your finger is touching in the last picture grab that with your index finger and pull it clockwise to cam over.
    if its closing all the way on the no go in the carrier shes alittle loose.

    TY for that. I'm pushing down on the cam with slight pressure until it stops. I'm not forcing it in anyway.

  12. #11
    Senior Member

    Member #
    4792
    Join Date
    Feb 2007
    Posts
    175
    Liked
    56 times
    Quote Originally Posted by 22many View Post
    Who's gauges?
    we should close this thread, we have too many postings about headspacing here already.

  13. #12
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times
    While I agree that it's an often covered subject. I haven't seen anything covering my exact situation.
    Do you have any insight, perhaps?

  14. #13
    Senior Member

    Member #
    4792
    Join Date
    Feb 2007
    Posts
    175
    Liked
    56 times
    Take it out and shoot it and look at the brass.

  15. #14
    Senior Member

    Member #
    20323
    Join Date
    May 2011
    Posts
    4,298
    Liked
    1149 times
    Quote Originally Posted by natlmatch View Post
    Yes Sir, that's exactly what it does, it barely moves when locked up with no gauge.
    No, try it without a gauge. Same play? Fine.
    WTB:

    Russian Type 1 or 2 parts/kit

  16. #15
    Member

    Member #
    23138
    Join Date
    Oct 2013
    Posts
    47
    Liked
    7 times
    Quote Originally Posted by robdog View Post
    Take it out and shoot it and look at the brass.
    RD,

    TY Sir, as it turns out I have some brass 7,62 so I'll head out this weekend and report back.

 

 
Page 1 of 2 1 2 LastLast

Sponsors

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Search tags for this page

There are currently no search engine referrals.
Click on a term to search our site for related topics.