Hornady: 300 Blackout 190 gr. SUB-X TAP, 20/Box



Hornady® 300 Blackout features a 190 gr. SUB-X™ (Subsonic eXpanding) bullet with patented Flex Tip® technology, specifically designed to expand at subsonic velocities yet meet FBI protocol. This cartridge is loaded with a powder that is optimized to provide flash suppression, clean burning, yet function in short barrel to carbine length rifles.



  • Ballistic Coefficient: (G1): .437 
  • Sectional Density: 0.286 Recommended Rifling Twist Rate: Best terminal performance achieved in 1:8” twist Characteristics: Polymer tippedExpanding
  • Muzzle Velocity (FPS) out of a LMT CQB 1:8" (8"): 1041
  • Energy (Ft/Lbs.) out of a LMT CQB 1:8" (8"): 457


  • 300 BLACKOUT
  • Match Grade Brass Composite

Powder & Primer:

  • Powder: Temperature stable with flash retardant 
  • Primer: Small rifle, Staked primer pocket


Ammunition Restrictions by State

No Shipping to HI or AK 

This item is restricted in certain states. Please make sure you are familiar will all laws in your area. Ammunition Restrictions.





Write a Review
  • 5
    190gr sub-x

    Its quiet and accurate. It ahoots perfectly in a 1 and 8 twist where more most 220gr subs fail. Perfect ammo for suppressed ar pistols or sbr's.

  • 5
    Hornaday Tap 300 blk subx

    We use this ammunition for night predator hunting and it performs great with both AR platforms and bolt action. It’s our primary choice.

  • 5
    Great for hogs and other predators

    Mile High had the ammunition in stock, and the first responder discount savings were much appreciated. We use quite a bit of this ammunition for depredation and varmint hunting.

  • 5
    Hornady 190 subX

    Most consistent subsonic 300blk I have found. Great groups.

  • 5
    Incredible accuracy

    One ragged hole at 25 yards from my PDW.