8 twist, threaded for brake or suppressor 1/2x28. Came off a lone peak action. Cerakote is 99%. ptg standard reamer, don't recall what that makes the freebore. Very clean work. Never got a great load done i.e. consistent .5moa, best luck with 143 eldx between .5-1" around 58 grains H1000. Ended up pulling it to change profile a bit on that action. About 200 down the tube. Start at $300 shipped obo.