Help with build- barrel, gas tube, etc

[Bigs28]

I would get my barrel from precision firearms. My 12" krieger shoots 8 shot 0.6 moa groups. I don't see the point in an 18" barrel other then "because that's what i want". A 16" will hit steel out to 500 np and the extra 2" isn't going to change much.

If your going to shoot suppressed i would go with some sort of adjustable gas. Either with the block or a bootleg adjustable bolt carrier. To me the cost of an adjustable gas block makes it a no brainer to get anyway.