Available configurations
| SKU | Grain | Bullet | Count |
|---|---|---|---|
| 80877 | 190gr | Sub-X | 20 |
| 80877B | 190gr | Sub-X | 200 |
About Hornady Black .300 BLK Subsonic
Hornady's Sub-X (Subsonic eXpanding) is designed to expand reliably at subsonic velocities — a challenge most hollow points fail at below 1000 fps. The 190gr bullet at approximately 1,050 fps is purpose-built for suppressed .300 Blackout. The polymer tip initiates expansion and the long-range cannelure holds the core together. The 200-round case offers significant savings over 20-round boxes.
Subsonic vs Supersonic .300 BLK
Subsonic .300 BLK (190gr Sub-X at ~1,050 fps) is purpose-built for suppressed shooting — it eliminates the supersonic crack and keeps noise levels hearing-safe with a good suppressor. Supersonic .300 BLK (110--125gr at 2,200+ fps) hits harder at range and is better for hunting or defensive use without a suppressor. Most suppressed .300 BLK owners keep both on hand. If you only shoot suppressed, subsonic is the whole point of the platform. If you do not own a suppressor, subsonic offers no real advantage over supersonic loads.
How It Compares
Hornady Sub-X is the most widely available factory subsonic .300 BLK and one of the few designed to actually expand at subsonic velocity. Sellier & Bellot 200gr subsonic FMJ costs less but does not expand. Magtech 200gr subsonic FMJ is in the same range, also non-expanding. Federal American Eagle 220gr OTM subsonic offers modest expansion. Out of a suppressed barrel, the Hornady Sub-X is the only one of the group designed to expand reliably at subsonic velocity.
Buying Tips
The 200-round bulk case (80877B) offers meaningful savings over individual 20-round boxes — typically $0.05--0.10/rd cheaper. Subsonic .300 BLK is a niche product and can go out of stock quickly when suppressor sales spike. Set a price alert if you are waiting for a case to come down in price. Note that subsonic loads will not cycle all gas systems reliably — adjustable gas blocks or suppressor-tuned guns run best. Test a box before committing to a case purchase.
Related
- All .300 Blackout ammo prices
- .300 Blackout subsonic
- .300 Blackout supersonic
- All Hornady ammo
- Best .300 BLK subsonic ammo — top subsonic picks for suppressed shooting
- .300 Blackout vs 5.56 for home defense — comparing these two AR platform calibers
- Subsonic vs supersonic ammo — when going subsonic makes sense