You may want to check out Lehigh Defense if you haven't already. It seems they have figured out subsonic expansion.The Annoyed Man wrote: ↑Tue Oct 01, 2019 4:52 pmI was initially big on the heavy subsonics too. I figured that the velocity/energy on target at close ranges would be on par with a +P .45 ACP. The problem is getting the bullet to do more than just poke a hole into something. I stopped relying on it for a subsonic HD rifle after I dug one of my own 208 grain A-Max out of the dirt berm at ETTS, which I had fired from about 25 yards away. All it did was knock the polymer tip off the bullet. Other than that and the rifling marks, it could probably be refired. After that, I’ve focused on supersonics ever since, and kind of given up on subsonics for now. When I can find commercially available heavy for caliber hollowpoints that will perform at subsonic velocities, I’ll revisit subsonics.der Teufel wrote: ↑Tue Oct 01, 2019 3:27 pm I have a Radical Firearms upper in 300 Blackout. I use it for hog hunting with a suppressor, but I don't shoot subsonic loads.
It was working pretty well for me for a couple of years, but the last two hogs I shot made it into the brush and weren't recovered. I'm hunting at night with a thermal sight. If the hogs get much more than 50 yards into the brush they're hard to find at night, even with a thermal monocular!
Previously I was using an AR-10 shooting .308 bullets and if I lose another hog I'll probably switch back to it.
I rate the 300 BLK as roughly equal to the 7.62X39 (AK-47) round. It's sufficient for hogs but shot placement may be slightly more critical than with a 6.5 Grendel or a 6.8SPC. My shots are typically around 100 yards or less, never over 150 yards. Remember, I'm not shooting subsonic loads.
My original intention was to use subsonic rounds when shooting at a feeder (generally 60-70 yards max range) but even there I've concluded that it's too underpowered.
Your Mileage May Vary. I'm just an average marksman. Someone who shoots better will obviously get better results.
But if the next hog I shoot runs off, the AR-10 is coming back out …
Back to the original question — I have had no problems with the Radical Firearms upper in 300 BLK.
Mine has a 10.5” barrel, with a 1:8.5 twist. The length is close to or right in line with original specifications for the cartridge. You don’t really need 16" to get all the performance you can out of it. OTH, it means either a pistol build, or a registered SBR.
https://www.lehighdefense.com/index.php ... -expansion
I haven't used their Maximum Expansion ammo but I have done some water jug testing on their Close Quarters. Seems to work as advertised.
From what little I think I know, hollowpoints generally need to impact a water-based medium to properly expand.