Cutting down an AR15 barrel

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  • MontereyC6

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    So, I've been searching for quite awhile for a SBR upper that is inexpensive and of good quality. I've been waiting for PSA to come out with some shorty upper, but from an email I got from them a couple of weeks ago, it's still going to be some time before they get any in.

    One of the fortunate things about my job is the availability of a complete tool room. I've almost talked myself into getting a 16" upper and cutting it down to 11.5". My question for you, is which upper? Will a midlength gas system PSA 16'' Hammer Forged Midlength Upper - 16" - Complete Uppers - AR-15 allow me to cut it down that much, or should I go with a carbine gas system? PSA 16'' Hammer Forged M4A1 CMV Upper - 16" - Complete Uppers - AR-15

    Thanks!
     

    MontereyC6

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    I would think you should prolly go with the carbine...but I'm not familiar with the exact measurements on the shorty's

    I have both a carbine and a midlength AR, and I'm pretty sure the midlength would work. I guess my main concern would be the different profile on the barrels. If I cut it off and rethread on a M4 style barrel, I think were the shoulder of the flash hider would be where the undercut of the barrel is. Going with a heavy barrel might be the thing to do.
     

    the1kidd03

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    I have both a carbine and a midlength AR, and I'm pretty sure the midlength would work. I guess my main concern would be the different profile on the barrels. If I cut it off and rethread on a M4 style barrel, I think were the shoulder of the flash hider would be where the undercut of the barrel is. Going with a heavy barrel might be the thing to do.

    yeah I think you're right....the 203 cut-out is right in the area you would want to thread.....should use a heavy barrel
     

    MontereyC6

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    I wondered about the gas port. The location wouldn't change, but a larger gas port would allow enough gas. Anyone have a clue to what diameter hole is needed?
     

    ctbreitwieser

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    Hey Monterey, in that email they sent you, did say exactly how long it might be until they get those shorty uppers in, or did they just a long time?
     

    ctbreitwieser

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    why not just build an upper?

    I looked a lot into building,and the price difference of cutting down a PSA, and unless you can find a cheap barrel and BCG for the build, I think the PSA is gonna be cheaper. And it will most likely be better quality than throwing together a bunch of random cheaply made parts to get the price down to equal PSA.
     

    MontereyC6

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    Hey Monterey, in that email they sent you, did say exactly how long it might be until they get those shorty uppers in, or did they just a long time?


    Here's the reply from them that I received on January 4.

    [FONT=&quot]We are expecting a large shipments of barrels to come in by this Mid-January to early February. We are also about to launch a new website that will allow you to choose different models of AR-uppers as well as other things. We apologize about the wait, but we are excited to do business with you in 2012. As we grow as a company we hope that we can continue to provide the best service to you as possible. Have a happy new year![/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Please let us know if there is anything else we can help you with.[/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Thanks for your inquiry,[/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Customer Service[/FONT]
    [FONT=&quot]Palmetto State Armory[/FONT]

    Hopefully that means they will be releasing them soon, but I'm not holding my breath.

    why not just build an upper?

    I looked a lot into building,and the price difference of cutting down a PSA, and unless you can find a cheap barrel and BCG for the build, I think the PSA is gonna be cheaper. And it will most likely be better quality than throwing together a bunch of random cheaply made parts to get the price down to equal PSA.

    What ctbreitweiser said. My original thoughts were to do a complete PSA SBR build. At their prices, I can't build my own(at least on the prices I've found). If I can figure out a way to shorten the barrel and make it work, I would be <$800 including the tax stamp. Not bad! I'm going to build a 9mm upper OBV8, I'm going to let you help me with that. ;)
     

    OneBadV8

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    I'm going to build a 9mm upper OBV8, I'm going to let you help me with that. ;)

    :rockwoot:

    I'm getting really close. It'll be ready to fire in about 4 weeks. Maybe sooner, just depends when I get it back from the engraver :ar15:

    Then in about 4 - 6 months I'll be able to throw a buttstock on it
     

    MontereyC6

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    :rockwoot:

    I'm getting really close. It'll be ready to fire in about 4 weeks. Maybe sooner, just depends when I get it back from the engraver :ar15:

    Then in about 4 - 6 months I'll be able to throw a buttstock on it


    It's gonna be SWEET! You'll have to pm your costs in that upper build. Then again, I probably don't want to know...:cool:
     

    ctbreitwieser

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    Here's the reply from them that I received on January 4.

    [FONT=&quot]We are expecting a large shipments of barrels to come in by this Mid-January to early February. We are also about to launch a new website that will allow you to choose different models of AR-uppers as well as other things. We apologize about the wait, but we are excited to do business with you in 2012. As we grow as a company we hope that we can continue to provide the best service to you as possible. Have a happy new year![/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Please let us know if there is anything else we can help you with.[/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Thanks for your inquiry,[/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Customer Service[/FONT]
    [FONT=&quot]Palmetto State Armory[/FONT]

    Hopefully that means they will be releasing them soon, but I'm not holding my breath.

    Awesome! I think I can hold out for that long.
     

    ryknoll3

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    You probably shouldn't use a midlength gas system for an 11.5" barrel. You'd only have 1.5" out in front of the gas port and that probably doesn't provide enough dwell time to reliably cycle. AFAIK there are no commercial manufacturers of mid-gas 11.5" barrels, so that would probably tell you it's not a reliable route to go.

    Also, if you use a M4 profile barrel you'd have to go down to 10.3" to get the proper barrel diameter to work with.

    I don't see anything in PSA's complete upper catalog that's going to allow you to buy a 16" barrel and cut it down to 11.5" as they don't have a standard profile 16" barrel.

    Also, the gas port on a 11.5" barrel IS bigger.
     

    Docjon

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    Sometimes when u go that short u have to open up the gas system. Not enough back pressure to cycle the gun.
     

    Dog1

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    why not just build an upper?

    This. I have built both of my SBR uppers.

    If you buy a barrel that is 11.5, then the port is already opened up.

    Get a White Oak Armory barrel with a Wylde chamber, the best of both 5.56 and .223.

    Here is mine, a 12.5 WOA barrel with a Wylde chamber, Spikes upper and lower.

    IMG_2414.jpg
     
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