ATTENTION - DUE TO DEMAND, CURRENT LEAD TIME ON 9MM & .223/5.56 FMJ IS APPROX. 3 DAYS

300 Blackout Subsonic Ammo | Fenix Ammo

Compare Fenix .300 Blackout products explicitly labeled subsonic. The documented assortment includes a 190 grain FXP load using a Hornady Sub X projectile and a 220 grain FMJ load. Both use 100 count packages and carry a Fenix-published velocity of 1,000 FPS. Projectile construction and Fenix product category distinguish the two choices. Both product descriptions also note that rifle configurations vary and may require gas setting or buffer weight changes.

2 products
.300 Blackout 190gr FXP Subsonic (100 ct.)
.300 Blackout 190gr FXP Subsonic (100 ct.)
$134.00
.300 Blackout 220gr FMJ (Subsonic) (100 ct.)
.300 Blackout 220gr FMJ (Subsonic) (100 ct.)
$108.75

300 Blackout Subsonic Ammo Guide

Projectile and Fenix product category provide the clearest distinction. The 190 grain FXP uses a Hornady Sub X projectile and is categorized by Fenix as defensive ammunition. The 220 grain option uses an FMJ projectile and is categorized as training ammunition. Both products are explicitly labeled subsonic, use 100 count packages, and carry a published velocity of 1,000 FPS. Grain weight alone therefore does not describe the full difference between them. Projectile wording and product category remain important catalog attributes. Those shared specifications do not erase their different projectile construction and catalog roles.

What the Subsonic Label Means

Federal explains that a subsonic loading avoids the ballistic crack associated with a supersonic projectile. That designation does not promise identical sound or function in every setup. Fenix states that both listed loads were tested in several rifles with barrel lengths from 8 to 10.5 inches, with and without suppressors. The product descriptions also note that rifle configurations vary and may require gas setting or buffer weight changes. These setup notes apply to both documented Fenix choices and should not be replaced by a category-level function assumption. Consult the exact product information and your firearm documentation.

Frequently Asked Questions

Which Fenix .300 Blackout products are explicitly subsonic?

Fenix explicitly labels the 190 grain FXP with a Hornady Sub X projectile and the 220 grain FMJ product subsonic. Both come in 100 round packs.

How do the 190 grain and 220 grain loads differ?

The 190 grain load uses a Hornady Sub X projectile and is categorized as defensive ammunition. The 220 grain load uses FMJ and is categorized as training ammunition.

What configuration note applies to both subsonic products?

Fenix says rifle configurations vary and notes that gas settings or buffer weights may need adjustment. Consult the exact product information and your firearm documentation.