Wanna get a semi 9mm AR with 16" at some point but I've noticed a lot of upper/lower play on all the Colt 223 rifles I've picked up and that bugs me. I have not seen the Rock River 9mm that takes modified UZI mags but I've played with Rock Rivers 223s and they are solid. Also, there's the B-Master Carbon series but I read on silencertests.com (I think) that it didn't work at all. Are the Colt 9mm mags expensive? Then it makes sense to go with RR.

Thanks for your input!

I went with the Rock River and have been very happy with the gun.  The 9mm's are everybit as tight as the 223 versions.  I have about 5000 rds through mine so far and it's still tight as it was new.

I bought the A4 version and stuck a Burris XTS-135 Red Dot, YHM Free Float Rail and a ARMS 40L on it.  



I bought 5 of the 25rd modified Uzi mags (all work flawlessly) and 1 of the 32 RD Colt mag (I'm planing on getting 3 more Colt Mags as money and other projects allow). Then I bought the 32 rd Pro Mag's from Natchez for $10 each for range use, then  The Pro Mags haven't given me any trouble yet, but I've only had them for a few months and I haven't shot them all that much.  I'm planing on another 500 rounds through it this Saturday which will all be throught the Pro Mags.

nice!  Looks like you got the pistol grip that SIG is gonna be putting on their 556!  Thanks for the info - please post back here on the Promags because all I've heard on Promag is CRAP.  That's cool on the RR, I thought that it would ONLY use the modified UZI mags but it takes Colt 32s also?!  Nice.  I like the shorter 25 rd UZI.

Does the magwell have the removable insert or is it fixed for 9mm?

Just realized that is an old pic, before I stuck the FF rail on.




I shot 200 rds of WWB Value Pack though the Pro Mags last night w/o any failures.  So far so good.  I'm still gonnd shoot a few hundred more on Saturday. The gun is just too much fun to shoot!


I have one that I have left loaded for about 2 months now and I can see any signs of the feed lips spreading apart.    They are looking like pretty good range mags.

colt/rra use the same mags


check out the rimfire&pistol caliber forum its a few below the ar discussion forum.