AR-15 9mm Question

[RonPaulSupporter]

Alright so I posted info regarding my AR-15 SBR build in the NFA section, but I'm starting to consider switching from a .223/5.56x45 to a 9mm. So my question is, if I use a standard AR-15 Lower receiver in .223, what do I have to do to allow it to fire with a 9mm upper?
Also, how difficult is it to build an AR using a kit and simply buying a stripped lower? I've never done it so if anybody could provide links to sites with instructions on how to do that I'd appreciate it.

Sorry about all the questions, but I don't own an AR-15, I've only shot them, so I really don't have any experience with disassembly, building, or anything like that. Thanks!

 

[Paul]

its is not hard to do. i havent ever built a 9mm ar15, but i built mine and have halfway put together ashylarry's on here. many people on here can help you out.

for the 9mm, you can use the regular lower and all the lower parts. Its just a different upper setup and different mags.

 

[Justus]

Assembling a lower is not hard at all.
Taking your time with the detent springs and properly installing the buffer tube are 2 tips that I can give you.


IIRC, you will need to modify the standard hammer in order to use a 9mm upper.
That may make the hammer useless for for using a standard upper.

The lower will also need to have a magazine adaptor that adds to the cost
of the build.

 

[ashylarry]

You will need a mag block, 9mm hammer, and buffer. I was looking into this also and it would cost about 650 + mag's for just the upper and parts if you already have a lower.

 

[RonPaulSupporter]

In case this helps anyone out with an answer, I'll explain what I'm planning to do. I'm buying the upper in 9mm (link below) after I get a registered SBR .223 receiver.
Welcome to Model 1 Sales' Online Order Center
Anyone have links to a place to buy necessary 9mm conversion stuff?
Again, this is only one option, I may just buy a standard lower receiver and have it registered as an SBR, then buy a 10 1/4" .223 upper. The only reason I was considering 9mm is because of the low cost, availability of subsonic ammo (if I put a suppressor on it), and the fact that you can shoot it at ranges that allow pistol caliber rifles/carbines.

 

[ashylarry]

Build Your Own 9mm AR-15 Lower at Ninth Stage



Just search google and you fill find a few sites selling the parts.

 

[RonPaulSupporter]

Thanks!

 

[shooter521]

The nice thing is that once you have purchased and installed your 9mm hammer and buffer, you can leave them in full-time (i.e. they also work with 5.56), so all you have to install and remove are your upper and mag adapter.

Be sure whatever mag adapter you get is set up to work with your existing 5.56 bolt catch. The 9mm bolt catch is longer and more fragile, and breaks frequently in dedicated Colt 9mm carbines and subguns.

 

[Justus]

The nice thing is that once you have purchased and installed your 9mm hammer and buffer, you can leave them in full-time (i.e. they also work with 5.56), so all you have to install and remove are your upper and mag adapter.

Be sure whatever mag adapter you get is set up to work with your existing 5.56 bolt catch. The 9mm bolt catch is longer and more fragile, and breaks frequently in dedicated Colt 9mm carbines and subguns.

Thanks shooter!

 

[in812]

Is it legal to put a 9mm upper on a SBR registered as .223 /5.56 ?woiuldnt you have to list the caliber as multi on the form 1 to avoid legal headaches ? I know thats a selling point for HK sear packs "registered in 3 calibers"
btw POF makes some real nice lowers and they say multi caliber rather than 223/5.56 just a thought

 

[bigcraig]

Is it legal to put a 9mm upper on a SBR registered as .223 /5.56 ?woiuldnt you have to list the caliber as multi on the form 1 to avoid legal headaches ? I know thats a selling point for HK sear packs "registered in 3 calibers"
btw POF makes some real nice lowers and they say multi caliber rather than 223/5.56 just a thought

1) It is perfectly legal to put ANY length upper in ANY caliber on your registered AR SBR. However, if you plan on changing the SBRs configuration on a permanent basis, it is best to send the ATF a letter with its new specs.

2) Listing "multi" as the caliber will get your form 1 sent back to you without approval and a letter stating that you must change "multi" in to a specific caliber.

That being said, you can list ALL possible calibers and barrel lengths on the form 1 that you intend to use, but why bother.

Just list the configuration that you plan on building first, but remember, the BATFE now demands that you be specific on caliber and barrel length, even if you buy a lower that is marked "multi".

 

[JimSwens]

I got most of my 9mm AR15 parts from 9mmAR.com They have the best prices I have found. And they ship quick.

Here's there link: 9mm AR-15

 

[Sailor]

Wouldn't this meet your criteria and be much cheaper?

CMMG AR15/M16 .22 Conversion Kit

 

[alexanjl12]

Wouldn't this meet your criteria and be much cheaper?

CMMG AR15/M16 .22 Conversion Kit

Since the OP is from July 2008. I'm sure hes set by now....

 

[Sailor]

I did not notice that! I would hope so.

 

[banjogore]

it's your money but you can get a new SUOMI 9MM SEMI-AUTO for less than $400.00 comes with a 36rnd stick but you can gat 71rnd drums for around $20.00... personally that's the way I would go