I know very little on this subject.  I do know that I could buy a Rock River , Oly, or other complete rifle in 9mm for around $1000.  Or I could buy an upper and futz with the mags, hammer, and other stuff, but it sounds like I'd have to dedicate a lower to just that one configuration.   Back to complete rifle.  Are there other not-so-expensive options for a 9mm carbine that can be suppressed?  

Oh, and if this isn't the right forum, could the mods move it to the most appropriate one?

Thanks,
MtnWalker

You could try to find a cheap marlin camp carbine in 9mm and have the barrel threaded or 3-lugged. Don't discount the AR upper quite yet. If you do some research in the pistol caliber forum you'll find that you don't necessarily need to dedicate a lower and that your hammer situation is not so cut and dry.

You could do a Marlin Camp carbine or buy an uzi for $650 and register it as an SBR for an additional $200.  

Or just pony up the $6,000 for a FA uzi and go from there.  

Quoted: i have one SBR lower, it has a Timney trigger in it, i use it for my .223 upper, 9mm upper with hytech block, and a .22lr upper.    i can convert to calibers in about 20 seconds.    the Hytech block just uses your std mag catch to hold it in, and it takes UZI mags which are cheap ($15-20).     BTW,,,the brl i use on the 9mm is a tros three lug, i also have a MP5 with a three lug and my next purchase is a SWR trident

Sounds like maybe you built your uppers?  I've looked around at some uppers at RRA's site.  what kind of accuracy do 10.5" barrels give - 4-5" groups at 50 yds?  75 yds?

Thanks,
MtnWalker