I got my SiCo Omega 9K out of NFA jail at the end of last week. I purchased the Harvester Direct Thread Plate (same threads as the Alpha DT mount, but shortens the whole mix by .5in). My POI shift was bit extreme, and it is because there are small shaves off of the end-cap upon bullet exit. When I say shave, I mean the ever so-slightest, but its leaving a small amount of material behind.
Bullet shaved can on bottom/left, sent bullets high and right several inches at 15 yards, increasing with distance.
No baffle strikes thankfully.
I tested same can on several pistols (swapped direct thread to piston) and had no issues whatsoever, and little if any notable POI shift at same or more distances, so it comes down to either the direct-thread mount, or the barrel threads not being concentric.
Low-hanging fruit is I bought an alpha mount direct thread (made specifically for Omega series), as well as a fixed piston drop-in, to see if either resolve the issue. Obviously I would prefer to leave the direct thread adapter in-place, but if the piston device works, perhaps I will go with that.
If nothing works, then it is a call to CZ CS to see what's next.
Any others go through this or similar? Advice?
TIA