This is a follow up to the first thread I posted about the new gas block (somehow it vansished).
Anyway I ran the S&B m193 through it on the #1 setting. It short cycled twice back to back. And remember that S&B is really hot ammo. I then turned it to the #2 setting and everything ran fine. I was shooting prone, and the casings landed about 8-9 feet away at 2 and 3 o'clock of my position.
So it looks like on the 11" barrel, #2 is as low as I can go. Don't know if it will be different for those of you who get the 12" barrel.