MDWS AR15 barrel chambered in .277 Wolverine. This is a 16 barrel. Threaded 5/8x24. Has less than 100 rounds fired through it. Comes with reloading dies, formed brass and a few loaded rounds. Uses standard 223 BCG and magazines and fits standard uppers. Parent case is 223 and is trimmed and shaped just like 300 blackout. This is a super fun and accurate barrel. I just dont have the time for it anymore.