Hornady® 300 Blackout Subsonic Ammunition is designed for accuracy and performance below the speed of sound. The new 190 gr Sub-X™ (Subsonic - eXpanding) bullet features a lead core. Long grooves in its gilding metal jacket combine with the bullet’s flat profile and the patented Flex Tip® insert within its hollowpoint cavity to help it expand reliably at low velocities.
Performance of the Hornady® 300 Blackout Subsonic load meets or exceeds FBI Protocol terminal ballistic test requirements.
I have used this round a couple years now and have cycled without issue from AR and bolt guns. Harvested 4 whitetails that I can recall from 50 to 90 yards. Have yet to see one pass through a deer but the farthest I've had one run once shot is 30 yards. So I would say it does pretty dang good. I see a lot of bad reviews but I've had good luck with them with well placed shots. I can see where a issue could come up if you don't place your rounds where they should go. But that's the same with all ammo.
I run this through a Seekins NXP8 pistol and a Ruger American Ranch Rifle bolt action, both suppressed. This round cycles the pistol perfectly and is accurate with both guns. I have yet to see how it works on deer but if it expands properly, it will be my go-to for sub-100 yard deer hunting and home defense.
Interestingly, the NXP8 eats everything except the Hornady 208 grain A-Max. Won't feed it properly no matter what I do. I was hopeful this 190 grain round wouldn't have the same issues, and, thankfully, it does not.
This stuff is awful. Every 2nd or 3rd round hangs up. Just go to Youtube and watch any of the test fire videos for it. I looked it up AFTER I bought 300 rounds. Dang it. It doesn't cycle correctly, the short wide soft tip hangs up on feed ramp.
It's the only ammo I've had an issue with in my AR pistol. Everything else shoots fine, it is not the weapon. In one video the guy adds a flaming pig and it works better, not perfect. I have an FP muzzle device, it makes very little difference.