[ARCHIVED THREAD] - 9mm Upper Internal Geometry

Posted: 10/9/2008 2:13:32 PM EDT

For those of you with 9mm uppers: Is there a cam pin cut out above the ejection port area like on the .223 uppers?

I want to build a slick side (no forward assist or brass deflector) .223 rifle with a flat top. The only uppers I have found with this configuration are the 9mm ones, but I remember someone posting that it was important to make sure they were cut on the inside to allow the .223 bolt to rotate correctly.

Can I install a .223 barrel and carrier group onto one of these uppers with no modification?

Thanks,
Augi

Posted: 10/9/2008 2:20:45 PM EDT

[#1]

ADCO can set you up with a 9MM upper that will take a gas tube. I assume this means they will take a cam pin too.

Posted: 10/9/2008 5:57:59 PM EDT

[#2]

Go with an upper from nodak spud, they specialize in retro style uppers and lowers.

Posted: 10/9/2008 7:14:16 PM EDT

[#3]

NDS makes no such thing. There is no retro flat top. I want a slickside without a carry handle so I can have a larger selection of optics to mount.

Posted: 10/10/2008 7:07:45 AM EDT

[#4]

Oops, sorry. I missed the flattop part. My bad.

Posted: 10/15/2008 7:18:05 AM EDT

[#5]

Get a RRA 9mm flat top. You will need to mill out the clearance for the bolt cam just as you suspected. You'll also need to drill a hole for a gas tube. I have a Colt 9mm upper that someone modified just like that for a 5.56mm conversion, apparently they didn't have any issues, but I bought it to use with 9mm.

Could always keep your eyes peeled for an early RRA uppers since apparently the first few ones out of the factory had both the gas tube hole and the clearance for the bolt cam.

Posted: 10/15/2008 8:04:48 AM EDT

[#6]

My RRA 9mm upper accepts a standard AR bolt and Ciener kit just fine. It just doesn't have the gas tube hole. I am still debating drilling it out myself.

Posted: 10/15/2008 1:35:46 PM EDT

[#7]

Why not just do a DPMS slick side upper ...... they are about 85 bucks or so ....

will work since its designed for 5.56 ....

no milling needed

Posted: 10/15/2008 1:37:30 PM EDT

[#8]

Quoted:
Why not just do a DPMS slick side upper ...... they are about 85 bucks or so ....

will work since its designed for 5.56 ....

no milling needed

Because it is an extruded 6061 piece of shit that weighs more than a stadard upper?

Posted: 10/15/2008 8:09:19 PM EDT

[#9]

ouch

Posted: 10/15/2008 8:29:09 PM EDT

[#10]

Quoted:

Quoted:
Why not just do a DPMS slick side upper ...... they are about 85 bucks or so ....

will work since its designed for 5.56 ....

no milling needed

Because it is an extruded 6061 piece of shit that weighs more than a stadard upper?

Tell us how you really feel lol..

[ARCHIVED THREAD] - 9mm Upper Internal Geometry

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[ARCHIVED THREAD] - 9mm Upper Internal Geometry

[ARCHIVED THREAD] - 9mm Upper Internal Geometry