9mm AR15 Build Ideas/Help Needed

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I’ve been putting together a 9mm AR-15 and I’ve hit a wall trying to find a lightweight 14.5” barrel. My idea is to add a barrel bushing or compensator that would increase the length to 16”. Anyone have any suggestions for a source?

So far, I’ve assembled a complete lower using a DDLES 9mm receiver and am still trying to decide on an upper and bolt/carrier. The American Spirit Arms side charger looks good and I'll probably use it, but I’m undecided on whether to use their carrier or a ramped CMMG, which would then have to be modified by ASA.

I’ve found that building one of these 9mm carbines is fun and not at all difficult to do, but finding some of the parts can be a problem. I think building a 5.56/.223 might be simpler.

I'd appreciate hearing from anyone with helpful suggestions and comments.


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Yankee Hill Machine has 9mm AR barrels, but not in 14.5". They have 16" fluted and threaded and non fluted, and they sell a comp for 9mm barrels too. Don't know those will make it as a lightweight.
 
Thanks everyone. I'm still at a loss about what to do for a barrel. I've looked at a great many 9mm builds online and noted what barrels some have used only to find that the manufacturer doesn't offer them any longer. I'll just keep looking. This is going to take a lot longer to complete than I originally thought....
 
Not trying to hijack, but could use relevant help that may add to the overall usefullness of this thread.

I am looking for a compensator/brake for my colt 9mm upper. Can anyone point me in the direction if one, other than YHM? Thanks much.
 
Not trying to hijack, but could use relevant help that may add to the overall usefullness of this thread.

I am looking for a compensator/brake for my colt 9mm upper. Can anyone point me in the direction if one, other than YHM? Thanks much.

It's relevant and I've been researching the subject too. Regardless of the fact that the 9mm probably wouldn't need a compensator, I think it's more useful than a muzzle break and we can't have flash hiders. The only other option is to have nothing, which would not look quite right. I've rarely seen an AR barrel without a muzzle device.

What's the thread pitch on your barrel? 1/2x28 or 1/2x36 TPI? If 28, then the Carlson Compensator is reportedly quite good. See http://www.carlsoncompsinc.com/index.htm . I've emailed Carlson and they will not thread for 36. The Carlson was somehow "improved" by Practical Solutions (see http://www.practicalpage.com/index.php?act=viewProd&productId=47 ) and available in 1/2x36, but the website says they're not taking any orders.

I'd like to hear what others have to say.
 
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My 9mm AR set up is with 16" barrel and a fake can running back into a free float hand guard.

The fake can adds almost nothing to overall length, and as already said, a compensator or break is really not needed.
 
i just want to say that is a KILLER lower. they say colt mags, but will uzi mags work as well? not like i can even afford this but i really miss my olympic 9mm AR. i take it then that you'd need an upper compatible with the colt system to run on one of these?

am i a retard and missed it in the thread--or is it just not posted what upper/whose barrel you'd use with this? or is that the OP's actual post?
 
My 9mm AR set up is with 16" barrel and a fake can running back into a free float hand guard.

A fake can is not something that I'd given any thought to. I'd like to see a pic of yours. Would a fake can be considered part of the barrel to make up the minimum 16" length?

I also like the free float handguard and am looking the JP Rifles modulars.

- - - Updated - - -

Last time I was at Umlaut Arms in Concord NH, he had them in stock, though it didn't show on his website.

Good to know. Thanks.
 
i just want to say that is a KILLER lower. they say colt mags, but will uzi mags work as well? not like i can even afford this but i really miss my olympic 9mm AR. i take it then that you'd need an upper compatible with the colt system to run on one of these?

am i a retard and missed it in the thread--or is it just not posted what upper/whose barrel you'd use with this? or is that the OP's actual post?

Thanks. Uzi mags will work with some slight modification. I have a few stashed away. It's almost impossible to find pre-ban Colts. I've had a WTB up for quite a while with no luck. A DDLES 9mm lower that runs Glock mags is also available.

9mm uppers are around and while the Spikes upper might have been my first choice, they are not being made any longer and used ones are impossible to find. I'm 99% sure that I'm going with the ASA side charger. Finding a barrel is my big problem right now.
 
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Contact Remsport I can help you with any questions you may have about 9mm AR's I have built a number of these guns and can pass along my experience. As far as muzzle devices I have been able to turn any 556/223 muzzle device into a 9mm device even rethreading.
Give me a call with your questions. We also have a large inventory of 9mm AR parts and can even build you a custom 9mm upper.
Thanks
John
413 579 1994
 
Very nice build. I would love to build one like that next year. Good luck with parts hunting I will be following this post.
 
and it's difficult to find a 9mm break to meet the MA AWB, not to mention with 9mm who needs one anyhow

You're right, nothing is really needed on a 9mm, but some like the look of a break, fake can or compensator. Also, finding a barrel without the threading is difficult, to say the least. 9mm barrels of any kind are not plentiful right now. Another option is to simply use a thread protector. I'm leaning that way myself.

To update my build, I've ordered the American Spirit Arms (ASA) side charger upper. They tell me that the BCG, which I've decided to use, is backordered, so I won't see it for at least 2 weeks. I'm actively hunting for a barrel now and have my eye on a 16" lightweight, but I have to make a few calls before I order it. The search for a free float handguard starts in earnest soon.

Later Update: Found a 16" lightweight chrome lined Shaw barrel. Delivery in a week to a week and a half. I should have it before the upper.

Later, Later Update: Barrel arrived in less than a week. Looks nice. It'd look nicer on a receiver....
 
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