Plus ce change, plus c'est le meme chose.
Your thread was what finally cemented the need to act on my SBR dreams. Over the holiday sales, I was eyeing that Sionics blem lower, thinking 'I really should just buy that, transfer it as a pistol, then build a shorty to SBR + suppressor host over time...' Delay and hesitation cost a man in this life, but I am patient.
After giving myself a crash course on gas ports, buffer systems, buffer weights, springs, and carriers, the overall answer appears to be the Sionics 11.5 with the Crane spec gas port mounted on an A5 lower (ie the Sionics lower... it's almost like these guys know what the hell they are doing, right?) with an LMT e-carrier helping even more. Given that your 11.3 with a sub .060 gas port was able to cycle, if not strip or lock open on lower pressure ammo unsuppressed, plus the anecdotal evidence and company testing from the Sioincs thread, all indicate that the .070 gas port is about the happiest medium between a reliable unsuppressed platform and a can-host as one can have without having to go into the contrivance of a switchblock. Which makes sense, given the origin of the specification: military SBRs that need to work with Mk262 and other full pressure NATO loads regardless of their condition.
As far as the KAC side of the business goes, I can understand the turn-key nature of it all. However, a Sionics upper + a lower of my choice kitted out with whatever grip/stock plus some BUIS still comes in cheaper/matching the price of the KAC upper alone, much less a full rifle. Further, I'll be building this as a pistol to start, then filing for the tax stamps. I am a lowly civil servant, and make actual dogshit for pay, which I then have to try and sell on the open canine fecal market (it's a real bear right now, I tell ya, that market). So, I have a real interest in spreading out the development costs of this project.
Thanks for the help and guidance thus far. This place is a treasure trove of good advice, experience, and knowledge.

