Factory aero precision 18" upper with KAK BCG with double ejectors and SLR Sentry 7 adjustable gas block. Was out this evening setting the gas block for function. Did the usual 1 round in a mag test fire. Had it set 6 clicks out from closed before tesf fire and ended up 7 clicks out from closed to get the bolt to lock back on empty mag. I noticed my brass in different places so I loaded up 3 rounds and fired away. The first round landed about 5ft away 3 o'clock. Next 2 rounds landed at my right at my feet. I'm kinda baffled. I have 10 AR's and built them all and have no issues with them as I've used quality components. This is my first 308 pattern AR. Not sure if I should look into the spring/o-ring of the extractor in this bolt. Or just run it as long as I don't get stoppages. FWIW, it's a factory M5 lower with a SOPMOD stock and Geissele SSA-E trigger. I plan on running my SD-N6 on it when I get it out of jail.

I have a Sentry 7 on my PA10 (have Faxon 16" pencil on it) and 7 clicks out was exactly what I landed on too (w/ weak 7.62 Nato. Always set your gas for the weakest ammo you'll shoot).
I wouldn't be too concerned about your ejection. So long as you're locking  back (and not more gas than does that), I wouldn't sweat it.