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Last updated November 11, 2026

.300 Blackout subsonic ammo prices

Suppressor-optimized loads under 1,050 fps. The reason most people buy a .300 Blackout.

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IronScout provides observed price and availability data for .300 Blackout ammunition across tracked online retailers. Data reflects historical price observations and does not include purchase recommendations.

These figures cover all tracked .300 Blackout listings, not only .300 Blackout subsonic loads.

Observed 30-Day Price (Per Round): median: $1.299, sample size: 6255.

Prices last updated November 11, 2026 · 295 listings tracked across 28 retailers · 31 days with data in the 30-day window

How we calculate this

SQL PERCENTILE_CONT over daily-best per-product-per-day observed in-stock prices

  • Daily-best is MIN(price_per_round) per (caliber, product, UTC day).
  • Only in-stock observations included.
  • Coverage varies by retailer and source.
View 295 tracked .300 BLK products →

.300 BLK subsonic options

Product LineGrainBulletCount
Sellier & Bellot 300 BLK Sub200grFMJ20
Magtech 300 BLK Sub200grFMJ50
Hornady Black Sub-X190grSub-X20—200
Sig Sauer 300 BLK220grOTM20
Federal American Eagle Sub220grOTM20

What to know about subsonic .300 BLK

Subsonic .300 Blackout — loaded to velocities below approximately 1,050 fps — is purpose-built for suppressed shooting. When paired with a quality suppressor, subsonic .300 BLK produces a hearing-safe report with dramatically reduced concussion compared to supersonic loads. This is the primary use case that drives .300 BLK adoption.

FMJ vs. expanding subsonic

The critical distinction in subsonic .300 BLK is between FMJ plinking loads and expanding defense loads. Standard hollow point bullets are designed to expand at velocities above 1,200 fps — at subsonic speeds (~1,000 fps), they behave like FMJ and pass straight through without expanding. This makes bullet selection extremely important for anyone using subsonic .300 BLK for home defense.

Hornady Sub-X is the standout expanding subsonic load. Its patented flex-tip design initiates expansion at subsonic velocity, something conventional JHP cannot reliably do. Lehigh Defense Controlled Chaos and Maximum Expansion bullets also offer subsonic expansion through non-traditional engineering (fragmenting or hydraulic designs).

For range and suppressor fun, FMJ subsonic loads from S&B and Magtech are typically the lowest-cost subsonic option. Save the more expensive expanding loads for your defense magazine.

Cycling reliability: Subsonic .300 BLK generates less gas than supersonic loads, which can cause cycling issues in some gas-operated semi-autos, particularly those with adjustable gas blocks set for supersonic ammo. If running a suppressed AR-15, ensure your gas system is tuned for subsonic or use a suppressor with back-pressure characteristics that aid cycling.

Related

Frequently asked questions

What is .300 Blackout subsonic ammo used for?
Subsonic .300 Blackout (loaded below 1,050 fps) is purpose-built for suppressed shooting. When paired with a quality suppressor, it produces a lower report than supersonic loads.
Which .300 Blackout subsonic loads are the common budget options?
Sellier & Bellot 200gr FMJ and Magtech 200gr FMJ subsonic are common budget options. These are FMJ plinking loads for suppressed range use. Expanding subsonic loads like Hornady Sub-X cost more per round. Current observed .300 Blackout prices are in the 30-day price summary at the top of this page.
Will regular hollow points expand at subsonic .300 BLK velocity?
No. Standard JHP bullets are designed to expand above 1,200 fps — at subsonic speeds around 1,000 fps, they behave like FMJ. Hornady Sub-X with its flex tip is specifically engineered to expand at subsonic velocity. Lehigh Defense also makes subsonic-expanding designs.
Will subsonic .300 BLK cycle my AR-15?
Subsonic .300 BLK generates less gas than supersonic loads, which can cause cycling issues in some gas-operated semi-autos. A suppressor helps by adding back-pressure. If running unsuppressed, ensure your gas system is tuned for subsonic or use an adjustable gas block.