OK, got my SBR lower ready to go - have a 9mm upper and will be getting a 45 upper at some point.  I want to suppress them both.

How short should I make the barrel?

If really short, where do I find FF handguards that will allow a very short barrel?

9mm will for the most part require 147gr ammo to run subsonic, so barrel length is not much worry, but I load all my 147gr ammo, and run the 10.25" Uzi, 8.5" on the AR, and 9" on the MAC, all these use my AWC Mk9 Uzi can.

45acp wont matter what length, as all 230gr ball is sub-sonic to begin with, but might be border line with barrel length and powder used.....

As to free float tubes, most are 2" OD, so most suppressors will set inside, you just need to decide what fits your plan.  I took a DPMS tube and cut it to fill the void on the MAC, as the AWC is 2"OD, so it had to butt up to the AWC.  Most cans are 1 5/8 - 1 3/4 OD for 9mm, you'll have to look at the various cans for measures.

So if it is a FF tube, then I can actually sort of screw the suppressor inside the FF tube?  What about the gas block?

Quoted: So if it is a FF tube, then I can actually sort of screw the suppressor inside the FF tube?  What about the gas block?

No gas block needed.
Like this:


Colt mag block, magazine, and suppressor are not for sale.  
Steve.

Somebody gots a Triple-X that'll pass 9mm, or it is there for picture purposes......

So the shorter barrel 9mm ar uppers DON'T need a gas block?  Is there a magical barrel length number that needs to be reached before I can get rid of the gas block?

OK, follow up question - you say MOST FF handguards and 9mm suppressors will allow for this set up.  Any inexpensive 9mm suppressors you can recommend?  I will also be wanting to use the 9mm suppressor with my HK P9S pistol - so I'm trying to figure out the best threading.  My pistol is already threaded 1/2 x32 rh - so I'm wondering if I should get the 9mm AR upper threaded the same way, or get an adapter for the pistol and use a more standard threading for the AR upper.

Quoted: Somebody gots a Triple-X that'll pass 9mm, or it is there for picture purposes......

It sures does, and it's very quiet also.  But too heavy to really use.

Steve.

The 9mm is blowback operated, no gas system period.

Steve.

Excuse my ignorance, but if I understand correctly the 9mm (and the .45 as well?) does not need or even have, on any manufacturer's upper (Oly, ASA, Colt) a gas block?  So the "gas block" on my 9mm upper is really just there for accessory attachment purposes (it has a pic rail)?

So I don't really need it there, do I?

Quoted: Quoted: Somebody gots a Triple-X that'll pass 9mm, or it is there for picture purposes...... It sures does, and it's very quiet also.  But too heavy to really use. Steve.

SO did you get the the Triple X Warrior and have it overbored for 9mm?

If so, how did it work in both applications?  Was the .223 AND the 9mm a good db reduction?

Quoted: Quoted: Quoted: Somebody gots a Triple-X that'll pass 9mm, or it is there for picture purposes...... It sures does, and it's very quiet also.  But too heavy to really use. Steve. SO did you get the the Triple X Warrior and have it overbored for 9mm? If so, how did it work in both applications?  Was the .223 AND the 9mm a good db reduction?

It's not a Warrior can, just one of the original Triple X cans from Mike Klos, it's close to the Warrior can, which I have also, as far as suppression in 5.56, the Warrior is better and in a smaller package (no 9mm usage thought, bore too small).  I like the Warrior for 5.56, very quiet on a 16" barreled AR, and would recommend the Warrior to anyone looking for an affordable suppressor.  For 9mm, I prefer the SWR Omega QD.

Steve.

Any experience with the AAC suppressors?  Specifically the Spider II?