Brand new in box, never shot or even mounted. Just ended up not being something I had the funds to pursue. 1:7.5" twist, 20", and made for AR-15. BSF makes some of the best carbon fiber barrel available, especially for ARs, would highly recommend. Let me know if you have questions. I've shot a couple matches with 6 arc, though obviously not this exact barrel, and can attest that if wildly outstrips 223 and 5.56 in almost every area.