5.45x39 build

Discussion in 'AR-15 Discussion' started by carnestopher, Mar 15, 2013.

  1. carnestopher

    carnestopher New Member

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    So my stripped lower was originally built up in my head as a 5.56 pistol but I've completely rebuilt it and am ready to start finding and ordering parts to build a 5.45x39 rifle. The only question I have is what buffer weight should I use?

    Another question is regarding corrosive ammo. I know that the barrel is the main concern, but is the gas tube at risk also?
     
  2. carnestopher

    carnestopher New Member

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    One more, for the 5.45 uppers, is there carbine/middy/rifle length gas systems? If so, what would the benefits of each be in a 16" barrel configuration? Sight radius from gas port is of no concern to me since I'll be running a Troy rail all the way down the barrel.
     

  3. Quentin

    Quentin New Member

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    Why are you making it hard on yourself going with 5.45x39, especially now when supply is short? Why not go with 5.56?

    I suspect you'll end up with carbine length gas and a standard weight or maybe H buffer. But I don't have first hand experience tuning that caliber in an AR.
     
    Last edited: Mar 16, 2013
  4. carnestopher

    carnestopher New Member

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    I have three 1080 spam cans from a trade a while back when I intended on getting a 74. I figure it will take at least 6 months to track down all of the parts and hopefully this ammo/parts panic will have settled down by then.
     
  5. carnestopher

    carnestopher New Member

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    Plus I already have my 5.56 set up the way I want it and with this ridiculous ammo shortage I only have just over 1600 rounds and I'm scared to burn through them. I have a guy that works at the local Academy to tell me when they get a shipment in but you can still only buy 1 box per day and that doesn't add up too quickly.
     
  6. Jriedy85

    Jriedy85 New Member

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    I love my 5.45. Much cheaper to shoot!!
     
  7. purehavoc

    purehavoc New Member

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    Heres some of my experience on the 5.45 stuff , buy the barrel and bolt from the same manufacturer, they dont all head space the same , a spikes bolt and another brand barrel did not head space together . Be careful if buy from 2 different vendors
     
  8. carnestopher

    carnestopher New Member

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    I've been thinking about going all Spikes but the stuff is impossible to find. I'm on every waiting list I could find. My lower is a stripped Shadow Ops Weaponry so I need to get basically everything else. This will be my first complete build.
     
  9. bluez

    bluez Well-Known Member

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    There is a complete Adams Arms piston upper in 5.45mm FS on vaguntrader right now.
     
  10. carnestopher

    carnestopher New Member

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    I have seen great reviews on the Adams Arms upper. Anyone have an opinion on them?
     
  11. 7.62 Man

    7.62 Man New Member

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    The guys at the range freak out when I start bump firing my 5.45x39 AR.:eek:
    [​IMG]
    They tell me things like, your wife will kill you when you come home without any ammo, or did you OK it with your banker to come up here & shoot.:D
    I just tell them that it is cheap ammo, because it is I stocked up back when it was about 9 cents per round.
    I have seen it recently as high as $299 per 1080rd spam can, when I bought in it was $98 per can.
     
  12. carnestopher

    carnestopher New Member

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    Okay so before work today I stopped by Legion Firearms to talk to them about ideas for the 5.45 build (since they declined my request to build it for me). The guy I talked to was super helpful and had a lot of great ideas but it got me thinking about all the little things that I overlooked like gas tube diameter, buffer weight, buffer spring, etc.

    Anyone have some hard data on some of the systems that other companies have come out with in the past like S&W and Spike's?
     
  13. locutus

    locutus Well-Known Member Supporter

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    S&W built a successful 5.45 in an AR platform so it can be done.
    \
    My 5,45 is a 74, but I dearly love the cartridge.

    Like you I "squirreled" away "several" Spam cans of 7N6 ammo at ~ $95 per can.:D

    I'd love to have a 5.45X39 upper for the ARs.
     
  14. carnestopher

    carnestopher New Member

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    I first intended to just buy a completed upper assembly but since I'll be slapping it on my first built upper, I just wanted to build the whole thing and put exactly what I want on it instead of modifying a factory configuration. I found an article on defensereview.com and the guy built a 5.45 AR and I think I'm going to copy it except slap a Troy Alpha 15" instead of his Daniel Defense 12"
     
  15. bluez

    bluez Well-Known Member

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    I just bought one used but in great condition.
    Paid MSRP for it.

    I feel strongly that the Adams Arm supper is a better choice for this dirty ammo with hard bimetal bullets compared to the Smith.
    The Smith has 4140 barrel and was chromed barrel and chamber.
    But I am really liking that the AA upper has the BCG and bolt melonited as well AND it uses 4150 steel for the (melonited) barrel.


    Put it on a spare lower I had lying around and mounted an ancient EOtech (build year 2k or 2k2 I forgot) on it.

    have not shot it yet since i just had eye surgery and am not supposed to shoot for another 2 weeks.

    5.45mm Ammo can still be had for around 18 cents a round so I got 2 cases.

    I still consider my other guns to be more premium and the AA upper doesnt feel as quality as a SR556 or SIg 516 upper of course but its also surprisingly light.
    And the piston components are melonited as well. :cool:

    I have not added an upgraded hammer spring to the lower yet.
    Dont know for sure if its necessary for sure but would prefer to add it before i go shooting..
    Reason is I dont want to drive 2.5 hrs ot our "range" and then find out my stock hammer spring in the lower is too weak to reliably ignite the surplus primers

    Anyone have a link to an in-stock source for the upgraded hammer spring??
     
    Last edited: Apr 28, 2013
  16. carnestopher

    carnestopher New Member

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    I would sure love it if anyone had a link!


    Also, when I add the extra power spring, is there any chance of a foul up with .223/5.56 primers if I were to put another 5.56 upper on it?
     
  17. sbeezy

    sbeezy New Member

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    I too am planning a 5.45 build but I'm having a hard time finding any parts when I do a google search. The best thing I've seen is a full upper from Model 1 Sales but I've read nothing but bad stuff about them There was also an upper on midway and I put myself on the notify list but it says it won't be available until january 2014. Lol. Have you had any luck finding parts?
     
  18. bluez

    bluez Well-Known Member

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    Find a local FS/FT forum in your state.

    There is always someone who want to sell a 5.45mm upper because their range wont let them shoot the 5.45 mm ( since it has penetrator)