I've looking at a 12ish inch length 6.5 pistol build and have a few questions.

Is 12" too short for a 30 omega can?

Will a 12" run suppressed without an adjustable gas block?

Is there a preferred bullet weight for the caliber/barrel length?  I load 6.5 Creed and .260 and have tons of 6.5 bullets laying around.  It would be nice to have something I load for but also can blast steel cased ammo through it.

Any issues with the Wolf ammo suppressed?

Thanks

Not sure about the omega can, but have been using YHM 30cal titanium cans on 12 and 16" Grendel, both with brass and tons of wolf steel case (particularly on the 12") with no issues.  In fact, I am not sure that I ever shot brass cased through the 12"

I think they make 6.5 cans but the. 30 cal will give you most versatility.

edit:  I do not have an adjustable gas block on anything, just heavy buffers.  12 and 16 are faxon group buy barrels from the 65G forum,  nitride.

there are several guys, myself included, that run an omega on a short grendel. you might be able to find archived threads about it, but i posted an email exchange with sico where they say they havent tested it shorter than 16", so that's the minimum known ok barrel length officially. He then got back to me after talking with the r&d guy who ran numbers and said it should be fine down to 10".

And even with shorter barrels than warrantied, you're typically talking about more wear on the baffles, not catastrophic explosions. The omega is a pretty robust can. Not as much as some others, but it isn't a slouch.

You might not want to run your short grendel full auto, but 12" has been just fine for my omegas. I also run my hybrid on a 9.5" 458 socom, and omega 9k on a 16" 223 bolt action, so I do like to live dangerously. ymmv.

Whether it'll run unsuppressed depends on a lot of factors.  Gas port size, ammo, etc.  My 12.5" Ballistics Advantage runs Hornady Black unsuppressed, but won't cycle Wolf steel case reliably without a can unless I use a standard carbine buffer.

FWIW I use a Sandman S.

ETA:. I see you asked whether it will run suppressed without an adjustable block.  I'll still say it depends, but probably yes.  Mine is 100% reliable with the can and I'm using a non-adjustable block.

I'm using 12" Faxon Group Buy barrel with .068" port, CLGS.

Bootleg Adjustable Carrier with Group Buy Monster Logo Bolt

Maxim PDW Brace with tiny 2.9oz buffer, heavy recoil spring

TBAC Ultra 5 .30 Cal Titanium Suppressor, brake attach

It runs all factory ammo suppressed so far:

90gr TNT (won't run unsuppressed due to recoil spring strength)
120gr Federal OTM Match
123gr Hornady American Gunner runs like a raped ape unsuppressed

Elander 17rd and 25rd mags
CProducts Defense 25rd mags

I’m running an omega on 12.5” with carbine length gas and standard gas block.

100% function with Hornady black and handloads with 123 SST.

Velocity with can runs 2200-2250.

I shoot my 12.5 ba barrel with an omega all the time with wolf. I've even run that upper on a rr and works great

Two 12" Grendel's well one is a 12.5" ,both with slr 7s running a surefire mini 762 gas setting on 6 has been fully reliable.  One is a BA Hanson and the other Xcaliber.

I queried SilencerCo, re: an Omega 300 on a 12.5" 6.5 Grendel. They replied via email a few days later, no problem with that configuration and warranty.. My Ballistic Advantage Hanson carbine length barrel (Carbine buffer) is leaning towards under gassed so am sticking with the Low-Pro pinned gas block that came with it.

Now if my Omega would be released from NFA jail, all will be right with the world....

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