As well as in shorter barrel lengths (~8″) the 300BLK is way top-quality for supersonics, not less than. Very long barrel 300BLK is close to pointless IMO, you could find other rounds that outperform it handily in exactly the same System, with same duration barrels. Stick to revealed facts only, https://300-aac-brass17159.blog-ezine.com/39170165/details-fiction-and-300-blackout-cases