I emailed with Joe today.  I had some questions about the MK9 can and the Bixler 3 lug mounts.  I mentioned the mounts not being available on the site.  He stated they have stainless versions in stock and are waiting on the titanium versions to finish.  He states the MK9 takes "the standard 1.375-24 Hub mount in the rear".

Amphibian, it seems you use the 3 lug mount on a variety of guns.  This can will likely see use on 5" 9mm AR builds (regular CMMG blowback and a CMMG RDB system) as well as an 8" 300blk build.  I'm currently leaning towards putting 3 lug mounts on all of these and having the ability to swap the can around.  I like the idea that I can run rails right up to the base of the can with this mount system as well.  Can you think of any reason I wouldn't want to do this?

Yeah he started doing Hub on them but I don't own any of those.  I personally would just get a solid Titanium Bixler rear mount w/ his SS Bixler nut for most use cases.  I also use dedicated UZI mounts but not a thing if you don't have an UZI.
Nope.  As you can see in the pics I've posted, that is how I run mine.  Some people have voiced concerns about being too short if shooting without the can mounted but you can always add some kind of 3 lug FH if you really think that is a problem but I don't.  Reach out to me if you need help with the barrels / 3 lugs so the adapter is threaded the entire length to eliminate a free bore condition that leads to fouling.

Thank you.  I just paid the invoice for the MK9 and adapter.  Joe put a SS Bixler adapter on the invoice (which I paid).  Since it'll be a while before I get the can (filing as a trust) I'm considering paying for a Titanium adapter and just waiting for it.  Aside from weight, the benefit of the Ti would be increased durability, correct?

I didn't know either. Agreed on the latter.

They mistakenly shipped me a SS hub adapter a couple weeks ago. It felt very heavy to me and seems to have a substantial wall thickness IMO. They exchanged it for the Ti, which felt lighter, but appeared to have the same wall thickness. Regardless, a much better fit for my intended can, a Ti CAT Mob. I'm very happy I switched it out.

Thanks for the info.  I emailed Joe again.  He said they're making a run of the Ti units next week, so he's holding my order until a Ti adapter is available.

Well it took longer than expected, but finally made it to the range with bixler mount and ca$h 9 set up on the CZ Scoprion.  I am more than pleased with both the Bixler mount and the ca$h9.  The mount is solid I ran just under 100 rounds through it  124gr, some 115dr and 147 gr.  I previously ran the CZ with a liberty cosmic which was ok but not great.  I did not do a side by side comparison but  to me the ca$h 9 was better in every way.    Should I chase something else down that requires a 3 lug, I would look at the Bixler mount again.  Although the wait time to get it was longer than I thought it would be as well I am more than satisfied with Shaw's performance of the mount.

deleted.

I chatted with Joe via email on 08/27 and he mentioned that they planned to run the 1.375-24 the following week, last week, and he sent me an invoice which I paid. Has anybody gotten a shipping notification from Joe for the titanium 1.375-24 mount?

I got a response from him on Friday.  Said the Ti Bixler mounts are starting the run Monday (tomorrow) and should be at Ceracoating by the end of the week.

I presume he is doing multiple runs as I got my Ti Hub Bixler mount about a month ago.  I know someone else that also got two of them.