The Hornady Subsonic .300 AAC Blackout 190gr Sub-X (brand part no. 80877) reduces noise and recoil enough to make it an ideal training round for new shooters, while still holding the accuracy serious shooters expect from Hornady. Hornady builds the Sub-X bullet’s Flex Tip, combined with long grooves cut into its gilding metal jacket and a flat bullet profile, to expand reliably at low velocities without losing accuracy. Unique powders formulated for subsonic use result in a low flash signature whether or not a suppressor is attached, and the round runs even quieter than a typical supersonic .300 Blackout load. In rifle ammunition for suppressed and subsonic shooting, this is Hornady’s dedicated Sub-X loading.

Key Specifications

• The chambering is .300 AAC Blackout, a cartridge built to run supersonic or subsonic loads through the same AR-platform rifle.
• The bullet is a 190-grain Sub-X, a Flex Tip design with long jacket grooves that aid expansion at subsonic velocities.
• This load is loaded to subsonic velocity, staying quieter than a typical supersonic .300 Blackout round even without a suppressor.
• Powders are specially formulated for subsonic use, resulting in a low flash signature.
• The case is brass, standard for reliable extraction and reloading.
• This is a centerfire cartridge, standard ignition for reloadable rifle ammunition.
• Each box holds 20 rounds, sized for a solid range or suppressor-testing session.
• Cases ship 10 boxes to a case, a useful bulk option for high-volume shooters.
• Cost works out to about $1.54 per round, reasonable for a specialty subsonic loading.
• The box ships at approximately 0.88 lbs, useful for planning a shipping order.

Frequently Asked Questions

Is this round quiet even without a suppressor? Yes, Hornady formulates a low-flash subsonic powder specifically for this load, making it noticeably quieter than a typical supersonic .300 Blackout round even unsuppressed.

Is this a good round for new shooters? Yes, the reduced noise and lighter recoil of a subsonic load make it a good training option for new shooters getting comfortable behind a rifle.

How many rounds come in a box? Each box holds 20 rounds of .300 AAC Blackout, with 10 boxes to a case.

Buy the Hornady Subsonic .300 AAC Blackout 190gr Sub-X, 20-Round Box

A suppressed rifle deserves ammunition engineered specifically for quiet, reliable expansion, and Sub-X is built around exactly that job. Load up before the next range session behind the can. Order from our Lubbock, Texas gun shop and it ships fast to your door.