RRA has a midlength handguard option on their 9mm upper. hope this is what your lookin for. piggy

CMMG can make whatever you want in 9mm. they have been working broducing their own 9mm line with Barrels made to order. cmmginc.com

I was going to do a 9mm dissipator in 9mm. It would be very simple. Just buy a 16" CAR setup and buy an RRA or Armalite clamp on weaver style gas block. Position the gas block with a handguard cap for long handguards....done. You may want to stick a proper size roll pin in the gas tube hole and through the handguard cap so your handguards have no chance of rotating. An armalite block fits for sure and I have heard that a RRA one will clamp on also. I realize the o.d. of the barrel is usually .720-.730 and the gas block area is .750, but it works just fine. Hope this helps.

Interesting thread!  Does anyone know if there is an optimum length barrel for the 9mm? It seems most applications are of the CQB type.  Is there a ("target") length barrel before the MV is affected by drag?

I would think anything over 10" is counter productive.  I'm planning my next barrel to be about 5.5" to keep the marginally subsonic rounds from popping (sonic crack).  There is no point in a long barrel 9mm because it is by nature a close range cartrige.  If you really want one that's cool, but I think you have to have a custom one made for you.  Good luck.

Sulley,Within the week I should have a used RRA 9mm 16"midlength barrel assy up for sale,Would work great for a dissy project...LMK....UNDERDOG

Paul556,
Thats what I was thinking too.  Actually I misread the initial post as someone wanting a 20" barrel.  The fact it was going to be clipped down seems to have escaped me.  I'd love a short one but it isn't allowed in MI.