OK, build has been complete for a few weeks and I've done the tedium of barrel break in. Fouling appears to have been pretty minimal. Here it is at the range yesterday:



Note that I've switched the trigger out for a CMC 3.5lb flat thanks to a sale at Primary Arms.

For break in, I've just been running my PST 1-4x24. Most of my range time yesterday was on ladders for my .223, but I did shoot 10 rounds of Federal Gold Medal Match 168gr SMK. Below is a 5 shot group @ 100 yards (ignore the 3 small holes from confirming zero of my RDS on a different carbine):



The last two holes in the bottom right were shot to round out total shot count (20 rounds total so far). They are also about .6 apart, center to center.

The PST has a 1 moa center dot, so I'm pretty impressed that I could pull off that group with that optic. It certainly bodes well for the rifle. I'm also pleased with the CMC trigger. Most of my ARs have Geisseles so I'm generally a 2-stage guy. It will take some more trigger time before I really decide on which I prefer.