Or, what should I look for?

The reasons:  Cheap plinking ammo/interchangability with my pistols.
                       I got some money to spend and i like new guns.
                       They look cool.

I recommend you post this in the pistol calibre section, seriously, i'm not trying to be a smartass.

Whats the effective range on those things?  

Oh, i didn't even realize that i was posting in the wrong area.

Build a RRA 9mm, they are reliable and w/ a reliable Colt 32 round mag, the bolt will hold open on the last round. They are cheap to shoot and easy to work with. You will enjoy this style weapon. Good luck w/ your next build!

I looked at a RRA and it was pretty damn nice. If I did not already have a Colt 9mm I would have bought it.
If you get one, spend the money and get good mags to begin with, and get the loading tool!!! I shoot 147 lead reloads for cheap and they are plenty accurate at 50-100 yards I shoot this at.

Colt 6450.

Olympic 9mm

Cheaper mags - Colt mags are quite expensive... Plus all you need is an upper reciever - it fits on your 5.56mm lower without any special hammers, buffers, etc...

The only 'downside' is that your mag release is on the lower-block (assuming you buy the upper half & use your existing reciever), not on your rifle...

Build your own. You'll be happier. Get a bolt (have it ramped at M60.com), regular hammer, and a Hahn loading block. Go with the bolt hold open option. The pro mags are Colt style mags and most of them work. C mag are going to do some metal Colt style mags in a few months. CMMG has a nice upper (chrome lined) and lower. Go with some KNS anti-roll pins and use a 9mm buffer from Rock River Arms. Then razzle dazzle it to you hearts content.

I only have one complete RRA 9mm flat-top so take this FWIW.

Immediately upon purchasing was less than overwhelmed.  I had initially purchased it to replace my Colt 6920 in the squad car with me but then realized, "The purpose of a handgun is to fight your way to a rifle" and I'm pretty sure whoever coined the phrase didn't mean a pistol caliber rifle/carbine.  I can also make a rifle caliber shoot short but it's a bit more difficult to make a pistol caliber shoot long.  

Another thing that peeved me was the cost of mags and their limited avalibility.

After not being able to sell the thing I decided I'd accept it and enjoy it.  Since that time I've come to thoroughly enjoy and like it.  I found cheap Uzi mags at Cole Distributing and had a friend who was a machinist in another life time cut them.  

I have yet to qualify with the 9 but will do so along with my other ARs so I can use whatever suits my fancy on a given shift.

My opinion is, if this is your first and only AR, get a 5.56 and then look to a 9 in the future.  If you're pleased with your 5.56 collection, then definitely get a 9.  They're great fun to shoot, are very accurate (in my experience) to at least 100 yards with WWB Value Pack ammo, and operate essentially the same as their rifle caliber brethren.

Long-winded and but one opinion, but since you asked,
Scott

You need to think about getting a SBR 9mm

Any other 9mm in a rifle length is a waste of time and money.

Colt 6450

Quoted: Olympic 9mm Cheaper mags - Colt mags are quite expensive... Plus all you need is an upper reciever - it fits on your 5.56mm lower without any special hammers, buffers, etc... The only 'downside' is that your mag release is on the lower-block (assuming you buy the upper half & use your existing reciever), not on your rifle...

+1

but not true.. SNS has a mag block that goes inside and uses the ar15 mag release, requires a modified mag, but the notching only takes seconds.

Quoted: Or, what should I look for? The reasons:  Cheap plinking ammo/interchangability with my pistols.                        I got some money to spend and i like new guns.                        They look cool.

COLT

Has any maker built a 9mm lower specifically as a 9?

Meaning- not a converted a 5.56/.223, and having a dedicated 9mm magwell.

Or are they all converts?

I thought I heard that MGI was going to make a 9mm mag well for their MLR. Word was it might take Glock mags too.  If anyone made a block or receiver that would take the Glock mags I would then do a 9mm SBR. If I wanted a 9mm right now I would get a Colt .

Anything ninemilipeter makes me want to vomit.......hat

10.5"

P.S. 9mm was originally intended to be a carbine round...

It's 'performance' is much better out of rofle-length barrels a/o 5" pistol barrels...

10.5 9mm SBR w/can  If that won't put a smile on your face you need help!

Quoted: Has any maker built a 9mm lower specifically as a 9? Meaning- not a converted a 5.56/.223, and having a dedicated 9mm magwell. Or are they all converts?

Bushmaster Carbon 9mm models do not use a seperate magwell. They are dedicated for 9mm mags.

I own a Colt 9mm with the mag well blocks pinned in.
I also own 2 different drop in mag well blocks.

First, you have to SBR a 9mm. You will like it.

Second, With Colt 20 and 32 round mags all 3 are very reliable.

With modified Uzi mags( purchased new and converted from Vector ) the pinned in Colt is the only
one that is reliable all the time.

If you can dedicate a lower to 9mm have the Colt 2 piece mag blocks pinned in the mag well.

i have no experience with 9mm carbines other than my colt 6450. i am totallt happy with it, and so is my 12 y/o son!
plan to sbr when i stop buying other stuff.

Thanks for all the replies. i currently have a very nice M4 type RRA/Bushy that i "built", so i was thinking of going the route of 9mm for my second AR type rifle.
I've always digged the look of the colts with that uzi mag hanging out the well, so it's beensomething i've wanted to own for a while.

Rock River.  

I bought mine in October of '04 and have ran 5,000+ through it w/o any problem.  I went with the A4 and stuck a Burris XTS-135 on it.  Even after adding the sight, a free float, ARMS 40L, KNS pins, JP Springs, badger tac latch, G27 grip and a OD Green refinish I still have under the cost of a Colt.

I've using the Pro Mags and Modified Uzi's as my range mags and keeping the few Colt mags in reserve.  The Pro Mags have been great so far, plus they are damn cheap!  

Quoted: 10.5 9mm SBR w/can  If that won't put a smile on your face you need help!

Quoted: Has any maker built a 9mm lower specifically as a 9? Meaning- not a converted a 5.56/.223, and having a dedicated 9mm magwell. Or are they all converts?

OLY



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