Polymer lowers

Discussion in 'AR-15 Discussion' started by WildMan225, Mar 10, 2012.

  1. WildMan225

    WildMan225 New Member

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    I'm in the process of building a new ar and I'm contemplating about using a polymer lower. Any feedback?
     
  2. jg3

    jg3 New Member

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    Why polymer?...go to PSA and get a stripped lower for around the same price
     

  3. ScottA

    ScottA FAA licensed bugsmasher Lifetime Supporter

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    Because it's stripped. More bang for the buck with polymer.
     
  4. jg3

    jg3 New Member

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    What s the price on the polymer lower...PSA has their stripped lowers for $80...I personally would avoid the polymer... especially to save only 30-40 dollars ...but again just my opinion, I don't have any experience with the polymer lowers
     
  5. Cattledog

    Cattledog New Member

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    I think AR lowers have enough drift pin issues without adding a weaker material to the problem. Not to mention the take down pins wear and tear. Then there's the flex. I would rather have the cheapest aluminum "off brand" lower before a poly one. I just don't see the cost savings either. Unless your looking at a $50.00 poly lower but at that price, I'd be wary of it anyway.
     
  6. AgentTikki

    AgentTikki New Member

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    A polymer lower sounds interesting to me, only time will tell if they are suited for the task. I remember how every scoffed at Glock back in the day......
     
  7. mjkeat

    mjkeat New Member

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    To much bad press out there for my liking.
     
  8. mjkeat

    mjkeat New Member

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    Nothing personal but you're exactly right when you say more bang but boom would be a better description lol.
     
  9. JTJ

    JTJ Well-Known Member Supporter

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    A complete with adjustable stock polymer lower runs about $120. The Plum Crazy lowers are made in Lake Havasu City. I think there are a couple of newer brands on the market now. I know they have sold a lot of them but dont know how they hold up. I do know of one that got run over by a truck and it did not hurt it. Just some scratches. I hear rumors of failures but no pictures. The only thing I have against them is they dont return my calls when I am trying to get donations to the FNRA. It would not hurt them to donate a lower for a raffle or auction. Charter Arms has been donating a Pink Lady for the past 3 years. I am hoping they see this.
     
  10. MrWray

    MrWray New Member

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    IMO, using a polymer lower would make the rifle feel cheap,and i dont see any advantages by using a polymer lower.
     
  11. mjkeat

    mjkeat New Member

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    All joking aside I may give one a try despite their reputation. I wish I could find a Cav Arms lower though.
     
  12. Cattledog

    Cattledog New Member

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    Yeah, a friend of mine checked out a plum crazy set up like that on Craiglist. Said he could flex and twist it in his hands. Call me crazy, but I don't think bendable materials and the AR platform are a good mix. There are plenty of polymer receiver firearms out there but they were designed that way from the beginning. $85.00 is a perfectly reasonable price for a stripped alum lower. Im not seeing how poly could be better in any way.
     
  13. AgentTikki

    AgentTikki New Member

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    [ame]http://www.youtube.com/watch?v=NaFevpTka-I[/ame]

    [ame]http://www.youtube.com/watch?v=_qpnmi3XPP8[/ame]

    [ame]http://www.youtube.com/watch?v=CEAYW_2y4VU[/ame]

    sorry guyz dunno how to embed vids....yet......
     
  14. EW1066

    EW1066 Member Supporter

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    I have watched that second video before and I can tell you that the methodology of their testing was biased to make thier lower look good. Sure they showed the amount of deflection, but what they didn't show was the amount of force required to create that deflection. I can say with some level of certainty that the composit lower would have been crushed to failure if subjected to the same FORCE required to compress the aluminum lower that much.

    As for the Glock comment. Glocks were designed from the beginning to be a composit structure. So its designed to play to the strengths of the material used. It cannot be expected that composits will perform better than a metal part when using the exact same form factor as the metal part. You must change the thiskness and form to play to the strength of the material used. Molding an exact copy of an AR lower will make it lighter but not stronger.

    When someone comes out with a composite AR lower that was designed from the ground up to be what it is, I'll take a second look. Until then they can keep them

    EDUB
     
  15. TacticalPrecision

    TacticalPrecision New Member

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    The only thing I didn't really like about that second video was the fact that they went off travel distance instead of pressure. It might take less pressure to cause the polymer lower to crack or shatter than it does for the forged, plus if the polymer shatters it's entirely worthless, you can always pry on the forged and try to make it spread back out a bit.

    As for the general feelings about polymer and feeling cheep, you're 100% correct! I had the opportunity to handle one at a gunshow from plumcrazy and it did feel incredibly cheap compared to a standard forged weapon. If you don't mind that, or you can learn to deal with it, they seem to be a pretty decent alternative to a standard forged.
     
  16. Cattledog

    Cattledog New Member

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    Yeah, Im not impressed with the "deflection" test. A pressure test would have been more telling. Better yet: Do a practical test (I cant imagine a situation where my magwell would be in danger of being crushed...wtf) and install the same buttstock on each receiver. Then mount the receiver in a vise and apply downward pressure to the buttstock until failure. A force gauge or just adding weights will tell that story. Show me that test. Still I have to ask "why." The poly AR lower is the answer to a question no one asked.
     
  17. Sniper03

    Sniper03 Supporting Member Supporter

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    I personaly thought the tests were pretty hokey! Nothing but a sales gimmick in my opinion. For one the hammer never traveled in its complete radius of travel the entire test. To me it was more a test of the Hammer and Trigger unit in the receiver. And nothing was mentioned about possible opening of the trigger and hammer pins holes in the receiver that could possibly occur if the Hammer had been functioning to full travel as it would in the real operation for 75,000 cycles. Then the press! Give me a break! Anyway if I were going to have to spend over a hundred dollars + on a polymer receiver I would certainly buy a good 7075 T-6 Aluminum Lower. The mention by one here on the thread of tolerances and flex of the Polymer Lower sure brings on another issue. And sure makes sense. Sometimes on the standard receivers we can have tolerance problems between the Hammer and Bolt Carrier Groups matching correctly. With any flex at all that could certainly generate more of an issue. No I am not totally against Polymer in the weapon industry since I have some Glocks and Springfield XD Pistols as well as a Kahr P-380.
    By the way as a little Armorer information. If you ever run into an AR that has been shot to the point that the Hammer and Trigger Pin holes are opened up slightly get a set of KNS Anti Rotate Pins. They will correct the problem. For those who do not know most Trigger and Hammer Pins do turn slightly in the receiver as the weapon is fired. Primarily the Trigger Pin. If nothing else I believe the lubricity of the Polymer surface would create less resistance to the turning. Only a thought!

    03
     
  18. Quentin

    Quentin New Member

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    Since the lower receiver is the "firearm" I'd like assurance that it will last. Last as in "a lifetime". And I like it to look good so I'll stick with 7075 aluminum. I side with EW1066 as far as original designs using polymer like the Glock and XD but will pass on a plastic AR lower for now, unless we're talking the S&W M&P15-22 (and even there I went with the Colt M4 .22 with metal receivers).
     
  19. WildMan225

    WildMan225 New Member

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    I'm building a (light) carbine. The polymer lower shaves a whole pound off the weapon.
     
  20. Quentin

    Quentin New Member

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    The polymer lower does NOT shave a pound off the rifle!