Magpul ubr + delton lower = problems

Discussion in 'AR-15 Discussion' started by BlackJack, May 16, 2012.

  1. BlackJack

    BlackJack New Member

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    So yeah, I just spent $270+ on a part I've been dreaming about forever. The Magpul UBR stock. And I have absolutely no complaints about it at all. But my delton lower is a piece of non-mil spec crap. The ubr doesn't fit properly and leaves a gap between the lower and the main tube assembly on the ubr. So my dreams were a little crushed. But, I figured I've been needing to buy a new stripped lower for quite some time, seeing as my pmags don't drop out of the magwel and installing a miad kit required alot of force and a dremmell. My dad's friend showed me his Spike's zombie lower awhile ago and I want that. It's affordable at $115. I just wanted to tell everyone that delton needs to get there stuff together, and ARE SPIKES LOWERS MIL SPEC?

    Btw the ubr will still function on the delton lower. The only problem is that because of the slight gap, it takes a little tension off of the rear takedown pin detent spring (which I broke during disassembly). So your rear pin will be a tiny bit looser.

    Idk the proper term for the hole in the lower that causes the problem, and I'm too lazy to google it. But it's the small circular hole cut into the outside of the lower right under we're you screw in the buffer tube. The ubr main tube assembly has a circular piece that fits directly into the hole and keeps the ubr from spinning around. Delton made the hole too small and the ubr won't fit in. It sits of the edges of the hole but not in it.
     
  2. mountainman13

    mountainman13 New Member

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    Yes spikes are mil-spec. They are a bit tough to get a hold of at the moment though. I've been keeping an eye out for a punisher lower for over a month now. They come into stock and sell out in a matter of minutes.
     

  3. JonM

    JonM Moderator

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    the ubr requires a shorter than carbine extension called an entry length extension tube that should have come with the stock.
     
  4. BlackJack

    BlackJack New Member

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    I know that. You can't put it on without doing that. I'm talking about the top part of the ubr stock, the assembly tube
     
  5. purehavoc

    purehavoc New Member

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    Got a few pics ?
     
  6. BlackJack

    BlackJack New Member

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    Not today. The problem isn't major. Gun And stock should function correctly with the small gap. If the problem is bad, then I will upload some
     
  7. Quentin

    Quentin New Member

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    So is there a problem with the receiver or not?
     
  8. BlackJack

    BlackJack New Member

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    Well I guess not. I was trying to say that the receiver is a little different than it should be.
     
  9. Fixer

    Fixer New Member

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    I have seen UBRs on almost every make of lower and never have I heard of this. I know I have seen atleast 1 DTi with a UBR and there was no gap. The only time I did see a problem with a UBR and a Lower was on a Mega Billet lower.

    What is bottoming out on what? Where isnt it fitting in properly. We know you are sdaying a gap...but why is there a gap. The tube should screw in flush if its the tube I think you are refering to.
     
  10. BlackJack

    BlackJack New Member

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    No not the tube you screw in, the tube that slides over the buffer tube. It doesn't slide all the way in to the lower.
     

    Attached Files:

  11. MikeJK

    MikeJK New Member

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    Did you check for obstructions inside the tube?
     
  12. BlackJack

    BlackJack New Member

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    There aren't any. It's not a big deal. If it is i'll be sure to find out once I get my replacement detent spring.
     
  13. purehavoc

    purehavoc New Member

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    Never mind I found a video and answered my own question
    . the guy tapped on it until it clicked and locked , did this happen with yours ?
     
  14. purehavoc

    purehavoc New Member

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    is the flat screw tight to the end of the buffer tube ? looks like if its sticking out the upper of the UBR doesnt fit flush


    [ame]http://www.youtube.com/watch?v=MrhFJA7LIjY[/ame]
     
  15. BlackJack

    BlackJack New Member

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    I followed the instructions to the letter and watched a video on installing it. The screw is very tight. Like I said, it shouldn't be a problem. Just pointing it out to everyone.
     
  16. BlackJack

    BlackJack New Member

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    Wait I didn't try tapping it. I thought about it but it wasn't in the instructions or video. I guess it won't hurt
     
  17. BlackJack

    BlackJack New Member

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    God I feel like a moron. Tapping worked........it's this kinda stuff that makes me feel stupid. But whatever. Thanks for the tip
     
  18. purehavoc

    purehavoc New Member

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    Let's see some pics with it on right now please :)
     
  19. BlackJack

    BlackJack New Member

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    I would but my camera is dead and my iPad pictures look grainy when I upload them
     
  20. purehavoc

    purehavoc New Member

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    No problem , Glad its fixed and it really wasnt a lower receiver issue, my buddies got a DTi lower and I thought his looked top notch and everything fit perfect on it when I put it together