Designed specifically for use in AR15/M4 firearms like the BANSHEE™ Mk4, .300 BLK not only provides ballistic performance that rivals its Russian 7.62x39 counterpart, .300 BLK excels in subsonic and suppressed applications above other common calibers as well. Best of all since this BANSHEE is built on the CMMG® Mk4 – AR15 platform, customization and upgrades like Drop-In Triggers are only limited by your imagination.