I want to do a 9mm build and not modify my magazines. I have a good bit of Glock and Uzi mags as well as sten mags . I have a complete normal .223  built lower. And assorted spares. I want it to be reliable first ..

Posted Via AR15.Com Mobile

Not sure what your question is. You mean how to run unmodified uzi mags? If so, you're going to need a Hy tech mag block.
It locks in using the ar mag lock and has its own uzi mag release. They're out of business but they show up in the EE from time
to time.

If you're asking "what do I need to run my current mags with my current lower?" then first I'll say that there is no Glock adapter to allow a standard AR lower to feed - the angles are wrong.  But DD makes a dedicated Glock magazine compatible lower for ARs, if you just have to use your Glock mags, but there really is no way to make a Glock mag, modified or not, work in a standard AR lower.

Second, the VM Hy Tech block for standard AR lowers is designed to allow use of unmodified Uzi magazines...but it seems to be hard to find right now.

Modifying Uzi magazines to run in a Colt-style 9mm carbine is straightforward, but needs to be done right, or the magazines will not work properly.  It isn't a matter of "scribe the mag through the mag catch slot then mill that space out."  If you are thinking that a Dremel is the way to do this, think again, and check out M60 Joe's web site,

Some people notice a bit of a hang up with AR modified Uzi mags in their Uzis, but I can't say if this is common or not. The two modified Uzi mags I got from Rock
River when I got my 9mm carbine run 100%.  But standard Uzi mags don't operate a bolt catch - which is something else M60 Joe can help with.