AK – remove your worst barrel pin (pic heavy)

Discussion in 'Build it Yourself' started by Boris, Aug 21, 2011.

  1. Boris

    Boris Son of Kalashnikov NES Member

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    Greetings comrades! May your glass be always full of vodka and the fire of pride for the glorious motherland burn bright in your heart. I am working hard on restoring a RomyG to its former glory, the time when capitalists and bourgeoisie trembled in their expensive baby seal shoes at the barrel of a AK47 pointing at them from the East.

    Barrel pins were put to retain barrels in the front trunnion and such a good job did the drunk bearded ladies of Romania, it’s easier to remove pipe from comrade’s Stalin’s mouth.

    I shaped a piece of steel to support the ornate shape of the trunnion, while I remove the pin with a chisel and a hammer. That did not work good. In fact I heard the pin laugh at me. I used air hammer and it did not move. I begged, I yelled, I went down on my knees and wept. I told it all about it’s mother, it’s sisters, grandmother and it refused to listen to me.

    [​IMG]

    I had to cover comrade’s Kalashnikov picture while I contemplated unthinkable … actually making right tools for the job! I have shaped a block of aluminum to mate with the trunnion perfectly like a Donkey Kong with Princess Peach. I have created a top plate so that I can guide a chisel completely drunk and can’t see where it suppose to go. Also, the top plate secures the contraption to the barrel, so when my hands are shaking with a hangover it'll line everything up.

    [​IMG]

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    Then I approached a 3 tonne press. It has a crevice in the ram which allows to hold steady a tool for the time’s when I can’t. I pressed and bent the cheap Chinese drill bit.

    [​IMG]

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    I decided to double the effort by going to a 6 tonne press. I drilled a ¼ hole in the ram to support a piece of ¼ drill bit as the punch. I pressed and bent the cheap Chinese drill bit.

    [​IMG]

    For a long time, a number 3.333333… appeared in my head. I figured that I need to increase the effort 3.33333… times and use 20 tonne press instead.

    ... yeah, I bent the pin. This time it was 1/4 drill rod tool steel. It pancaked under pressure.

    [​IMG]


    I was desperate. I have offered comrade Kalashnikov an entire bottle of vodka in exchange to the secret to remove barrel pins. I studied the knowledge of web. What made a lot of sense are two methods to remove barrel pins. One was to use a HF vise made by comrades in China, clamp the trunnion with a pin pressing on it, tighten it and hit the vise like a red headed enemy of the people. Then I heard comrade Flintoid speak of hitting the top of the arbor press and it all made sense. As you hit the chisel, it will resonate, slip and otherwise dissipate the energy of a perfectly good hammer blow. I figure that three things must happen:

    1. You need a heavy anvil that will not bounce away easily under a strong blow.
    2. You need to press the chisel to the pin hard, so that the energy of the hammer blow will transfer elastically straight to the pin.
    3. You need to hold entire jig together while holding your glass.

    so I have created this contraption. The thing that looks like comrad Stalin's sex toy is the anvil. Two 1/2 bolts secure the top plate which holds the punch that was ground down from the air-hammer.

    [​IMG]

    I sprayed the threads with some WD-47 and tightened ... how you say it? ... the p*ss out of them.

    [​IMG]

    now, I do not kid you. I took one swing with a 4# hammer, a child's toy, and the pin moved. I was so happy, I took the barrel out of the rig and tried to use regular punch. No luck. I got nowhere. Back in the rig, it took few swings of the hammer to drive the pin completely out.

    There was something, I don't know what in the hole, it ripped the groove in the pin as it moved out. If you stare at these two images, you will see what I mean in 3D:

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    This shows you how a bottle opener and a hammer (... and comrad Stalin's sex toy) can hasten the triumph of world communism!

    [​IMG]
     
    10 people like this.

  2. Yep, a BFH is the best way. Haven't had one yet that took more than three hits to drop out.

    If its all galled up be sure to dress it up before you reinstall.

    If you haven't driven the barrel out yet, check the pin hole and clean out any galling in there beforehand so it doesn't damage the trunnion on the way out. Don't open up the barrel groove or it will effect your headspace when reinstalled. Just push out any large debris.
     
  3. radioman

    radioman NES Member

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    How come every time I hear anything about an AK the first thing said is how simple they are??? From what I hear on NES they seem to be a royal PITA?? I'll stick with my very simple AR!
     
  4. Dream to Dream

    Dream to Dream Member

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    I am comfortable saying with the utmost confidence... if you and Flintoid ever work together on a build and co-create a thread describing the debacle, we can close the Epic Thread link in the Member's Section because there'll be no topping that. Between you and Flintoid, I've actually injured myself laughing too hard.
     
  5. Donvin999

    Donvin999 NES Member

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    You sir are hilarious!!! When I decide I must build me own ak thinking of a psl actually I must buy u a bottle of vodka!!!
     
  6. flintoid

    flintoid Banned

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    toys are pretty easy to assemble.
     
  7. [laugh2][laugh2][laugh2] True!
     
  8. akma

    akma Member

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    When trying to remove these tough pins the SHORTER the punch the less likely it will bend. The more force will be transfered downward where you want it. It's better to get the stuck pin moving with a short punch then use one a little longer and so forth till the pin is removed.
     
  9. xtry51

    xtry51 NES Member

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    LMFAO, awesome post Boris.
     
  10. beaker

    beaker NES Member

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    Hilarious, well done.

    Sent from my Droid using Tapatalk
     
  11. Lip

    Lip Army Veteran NES Member

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    Great post comrade the party is pleased.
     
  12. SKS Ray

    SKS Ray Moderator

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    You must spread some Reputation around before giving it to Boris again.

    I have to think that if we had the old rep system Boris would have reached Double World Champion by now.
     
  13. Twigg

    Twigg Member

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    Comrad Kalashnikov would be proud !
     
  14. atilla

    atilla Member

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    or better yet hero of the soviet union.

    awesome thread. i laughed at all the bent metal, you guys really should have seen the exploding drill bits that flintoid and i had, too.
     
  15. flintoid

    flintoid Banned

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    Derek should add that to his user name title. I am all for this.
     
  16. NickW85

    NickW85 NES Member

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    I felt like reviving an old thread. I was removing my barrel pin today and if yours is being rather difficult it could be the method in which it was installed. My pin was flared after being installed back in the 70s. The BFH approach was a BF(joke). The best way to remove these is to take an undersized drill bit about 7/32" and drill out to a depth of 0.15-0.2". This will remove just enough material to re-leave the flair when removing the pin. The pin can still be reused but for $5 why not just use a new one. A new pin is always nice to if your going all they way and reaming you new pin hole.

    Even if you don't use this method you now know why the pin extraction process is difficult for the barrel pin.

    Boris, Awesome thread!
     
  17. flintoid

    flintoid Banned

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    If your barrel pin is flared on one side, why not just push it out of that side? Then you don't have to move the flare through the barrel pin channel.

    These pins are not uni-directional. They are not tappered. They will move out of either side of the trunnion.
     
  18. NickW85

    NickW85 NES Member

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    Some are flared from both sides I'm guessing. Mine specifically had punch marks on both sides to intentionally flare it. It wasn't a lot but it was enough to make it difficult. I have to head-space it anyways as the trunnion was on a cut barrel an not on the barrel I'm going to use, so I had nothing to loose by drilling the pin. But I know what your saying. Its the first of hopefully many barrel pins I will be removing.
     
  19. flintoid

    flintoid Banned

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    Interesting. I've never seen any intentionally flared barrel pins. My guess would be that the person that demilled the rifle first tried to remove the barrel in a traditional sense and failed. Is it a Romanian kit or another country of origin? And was it bought privately? This could explain the pin flares.

    I've done 20-30 barreled rifle kits and none of the pins were ever flared. Some pins have a bit of a chamfer on one side to aid in assembly, but that is all. And a few had debris in the pin channel like Boris' bad luck kit. Those are monsters to remove.
     
  20. NickW85

    NickW85 NES Member

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    It was a psl kit from centerfire systems. Each end of the pin had 3 punch marks and once removed the pin still had a flare to the side I didn't drill. I thought it was weird since I never read anything about people having flared pins.
     

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