Hornady Subsonic .300 AAC Blackout 190gr Sub-X Ammo

Description

This Hornady Subsonic .300 AAC Blackout load pairs precision engineering with real-world performance. At 1050 fps, it stays below the sound barrier for that Hollywood-quiet operation when paired with a suppressor, while the 190 grain Sub-X bullet handles the expansion challenges that stump ordinary subsonic rounds.

Understanding the Sub-X Bullet Design

Traditional hunting bullets tend to fail at subsonic velocities, but Hornady engineered the Sub-X specifically to overcome this limitation. The bullet combines a soft lead core with a gilding metal jacket featuring long grooves that promote expansion without sacrificing penetration. The patented Flex Tip polymer insert sits in the hollowpoint cavity and initiates expansion when it contacts soft tissue, creating effective wound channels while maintaining the structural integrity needed for medium game. This design expands reliably down to around 900 fps, which gives you margin for energy retention downrange.

Optimized Powders and Brass

The propellant selection matters as much as the bullet in subsonic loads. Hornady selected powders specifically tuned for velocities below the speed of sound, which not only achieves the quiet performance but also produces a low flash signature whether you're running suppressed or not. The ammunition uses fresh Boxer-primed brass cases loaded to consistent pressure specs. This attention to detail shows up in consistent feeding and reliable extraction round after round.

Why This Load Works Both Ways

Yes, you can run this in unsuppressed rifles too. The 1050 fps velocity stays subsonic either way, keeping that reduced report and manageable recoil. But pair it with a quality suppressor and you get something special—the kind of quiet that makes fast follow-up shots feel almost casual. Performance testing shows this ammunition meets or exceeds FBI Protocol terminal ballistic requirements, so you're getting proven terminal effectiveness, not just a quiet round.