AR15 buffer tube/ take down pin problem

Discussion in 'Gunsmithing Forum' started by Firecontrol663, Feb 7, 2014.

  1. Firecontrol663

    Firecontrol663 New Member

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    Hello everyone, I am new to this forum and this is my first post. I hope I am posting in the correct area.

    I am new to AR15ing and am currently building one. I have a Colt AR15 .223. I recently installed a carbine stock to it and replaced the buffer tube. Everything is fine and feels good. When I pull the charging handle back with the take down pin pulled out it is very easy to rack back. When I push the take down pin in and pull the charging handle back it's very hard to pull. I don't understand what the problem is. Does anyone have any idea?
     
  2. KG7IL

    KG7IL Active Member

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    Welcome to the Forum.

    Please stop by the Introductions http://www.firearmstalk.com/forums/f2 and introduce yourself. You will be met by the welcoming committee

    Unless I am misunderstanding, the resistance would be the buffer spring. That is, IF the upper is swung open with the pin removed, and IF the upper is closed with the pin installed.

    If this isn't the case, let us know.
     

  3. JonM

    JonM Moderator

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    Did you also get a carbine buffer and carbine buffer spring??

    If your using the original rifle length as I'm assuming that's what you had since you didn't give us pics or a model number to go by... its not going to work that way

    Colt makes and has made a LOT of different models ar15. Saying colt ar15 can mean a lot of things as they have been making them for half a century
     
  4. danf_fl

    danf_fl Retired Supporter

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    It almost sounds like the bolt carrier is scraping on the pin (out = easy, in = hard).

    When you disassemble for cleaning, get a punch the same diameter of the pin and see if the carrier rubs on the punch.

    In other words, try to duplicate the problem without the lower attached.
     
  5. JonM

    JonM Moderator

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    The takedown pin itself doesn't interact with the bcg in any fashion. The rear one has a detent that is held in by the a2 stock or endplate.

    Sounds like the wrong buffer/spring/tube crossthreaded or tube screwed in too deep. Or combinations of those
     
  6. KG7IL

    KG7IL Active Member

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    To our OP, Firecontrol663

    Again Welcome to the forum. . .. come back. help us to help you..... where are you?

    We need some info on how, when this happens.
     
  7. danf_fl

    danf_fl Retired Supporter

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    Are you sure the BCG is installed correctly (not upside down)?
     
  8. KG7IL

    KG7IL Active Member

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    I'll admit, I just tried this. Didn't think this could happen.
    I still don't think this can happen. (Unless I shear off a few parts).

    I understand his question to 'hinge' on the pin.
    I don't think that an upside down BCG would EVER MOVE EASILY. .. .
     
  9. danf_fl

    danf_fl Retired Supporter

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    New people have done a lot of things I never thought were possible.
     
  10. sgthooah04

    sgthooah04 New Member

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    I would go with JonM. If the upper and lower are together when the pin is in I would look at the buffer assembly. I Would also look at the buffer retaining pin to see if it's too long haven't had a problem like that but I have gotten a few parts and springs that wouldn't work in different manufacturers guns.

    Sent from my SCH-I545 using Firearms Talk mobile app
     
  11. SGTRud

    SGTRud New Member

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    I am going to go with this answer as well. The buffer retainer pin should only be as long as needed to hold the buffer in place. If its too long, it could hit in the rear of the bolt carrier, or rub on the bottom. If you think either of these are happening, check your bcg. Pull it out and look at the rear, you should see a little indent where you have been pulling the carrier into the retainer pin, but thats as far as it will go if its a complete obstruction. If its rubbing, you should see a line scratched into the channel of the carrier where the retainer will follow during normal cycle of the weapon.

    If it is too long, there are two basic things you can do. 1st is to purchase a new one that is a tad smaller, or use a stone and file to shorten the length of the pin. If you file it down, make sure to smooth it back out with very fine sand paper.
     
  12. purehavoc

    purehavoc New Member

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    I think he is just feeling the tension of the buffer spring which is normal . Dont be a sissy , rack that ol girl like you mean it . Pull it back and let it go . Dont try to ride the BCG back home , release and let her slam home .

    When he removes the rear takedown pin , it moves easily . Yeah when you have the upper open no spring tension .
    When you lock it down you have spring tension .
    This is simple there is nothing wrong with it . The buffer pin is either engaged with the buffer tube or its gone .
    I think you are all over thinking this one .
     
    Last edited: Feb 11, 2014
  13. KG7IL

    KG7IL Active Member

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    Hello FireControl...... we need you back!