Hornady 255gr 7.62x39 subsonic

General Firearms Reloading & Ammunition
1

To my knowledge, subsonic 7.62x39 that will reliably cycle a rifle hasn’t really been available. I think this coupled with past reliability issues associated with running 7.62x39 in AR15’s is what gave rise to 300 Blackout. Hornady is now offering a 255gr subsonic 7.62x39 load.
https://www.hornady.com/ammunition/rifle/7.62x39-255-gr-sub-x-subsonic#!/

I’m interested to hear if anyone has used this ammunition. If so, how did it perform? Does it actually cycle rifles? If it runs well, I’ll actually take the leap of getting a 30Cal suppressor.

2

The real question is will it stabilize with typical AK twist.

3

This has been my question. I’d like to get a pile of it, though for $2/round I won’t be doing that any time soon. At some point I’m going to get a couple boxes of all the subsonic x39 I can find and try them on paper at 3 to 25 yards to see if I get any keyholing.

4

My thought regarding testing other 7.62x39 is that it doesn’t matter if it won’t reliably cycle the action of the rifle it’s used in.

5

From what I read, all the newer subsonic 7.62x39 rounds claim to be able to cycle. I imagine this to be true, and even more so if using a traditional baffle high backpressure suppressor.

6

What were the issues with the Brown Bear subs that have been out for a while, but always seem to be out of stock?

7

Today I put 20rds of the Hornady 255gr subsonic through my Colt CR6762. Ejection was about 8’ to about 4:00 and it locked back when the magazine was. I’ll try it in an AK next with a suppressor, but just wanted to use the Colt AR15 as a baseline.

8

Sweet; thanks for the follow-up. I’m considering doing a x39 AR around a custom barrel…. Any chance you know what the projectile diameter mikes at? As in .308 vs .311

Edit: from Hornady’s website, looks like .311, with a B.C. between that of their two lighter .308 SubX projectiles. Flat based.

9

Our buddy has a suppressed subsonic set up that runs great. I’ll have to ask him what the ammo is.