EDUCATE ME PLEASE - suppress AR pistol vs suppress 9mm PDW???

never been down the road of suppressing anything and unlike my firearm purchases over the years, I really want to get this right from the start...

I read just about everywhere that most suppressors for 223/556 are made for barrels OVER 10.4inches... but mine current setup is 9inches and ultimately would prefer a dissent with 6.5inch barrel.
I understand the loss for 223 / 556 but even at 6inch barrel, it is still more powerful than a pdw in 9mm by at least 100 FPE.
problem is that it is TOO LOUD.

So - can you suppress an AR pistol with 6.5inch to 9inch barrel without ruining/ degrading your suppressor baffles prematurely? Is there one that does this?

I'm not wanting this setup for long range, this would be for home defense and well inside 50yds.

At that point, do you just skip it and go 147gr 9mm suppressed PDW to keep the noise down and take the 100ish-FPE loss?

My only calibers are 223/556, 9mm - so 300blk, 5.7 etc is not something I want to entertain, dont want to start adding another caliber.

Anyone been down this rabbit hole?

Stupid quiet is achieved with a velocity under about 1060fps or so. That's 9mm level. 556 is going to be 2800-3300 fps and it will still be loud and have a crack down range.

What are you trying to achieve?

Agree^ looking at some data tables, 147gr 9mm stays under 1100fps regardless of barrel length, whereas 223 55gr is approx 1995fps from 6inch and 2400fps from 9inch... I like the fpe of 9inch 223 55gr from 9inch vs 9mm 147gr - it is literally double the energy BUT how much louder is that "crack" you mention?

Is that 2400fps 223 - if suppressed - hearing-safe or not at all?

Doubt you will get hearing safe with 5.56 out of semi auto.

So inside 50yds and esp for home def it sounds like 147gr 9mm suppressed... always. The doubled FPE appears to be a benefit to the suppressed AR pistol that is not worth it (way too loud for home def/ cqb) when double tapping a 9mm gets you there-ish if needed at all.... I'm not understanding why I see all these suppressed AR pistols - other than flatter shooting at longer ranges (but in an urban-issue setting, who needs that??)

Shoot 147 or up subsonic ammo. In 9mm. You’ll be hearing safe.

Remember most 9mm cans are meant to be used on a pistol so make sure you get the proper piston set up for a carbine.

I don’t even concern myself with barrel length in 9mm it’s such a low pressure round when compared to 556.

I’ve got a dedicated 556 that is one of the quieter cans on the market and it’s not even close to hearing safe. I’ve shot a 30 cal can on a 556 as well and same thing.

I don't believe there is a suppressor out there that would ever make a AR pistol "hearing safe". I have a Saker 556 for my SIG SBR and I can get by with GOOD ear plugs but not for long shooting sessions. I agree with the others, for what you want go with a 9mm AR pistol with subsonic ammo and that should suffice for a home/vehicle PDW. And you can always pull the suppressor and go with "hotter" ammo if needed.

There are a few 'custom' manufactured 5.56/.223 subsonic loads that are like $1 or more/round, but they won't cycle any semi-auto and generate like 150 ft-lbs at the muzzle. That is less than half the energy of readily available subsonic 9mm for about .30/round.

I'd certainly go 9mm.

I'm thinking 9mm 147gr for HD strictly and AR pistol with Witt machine SME for outside...

I'm considering a DA wolfman, especially considering it can run 556 w keymod/ sacrificial muzzle device