Anyone hand loading subsonic Hornady 255gr Sub-X’s in their 7.62x39’s yet?

[BALLISTICJESUS]

I picked up a Ruger Ranch 7.62x39 (16") just for shooting the Hornady 255gr Sub-X bullets. I have a bunch of the bullets and a pile of Starline 7.62x39 brass. I haven't had the time to start working up a load yet. I'm going to run it with a Silencer Co Omega 36M. It should be fun for Rockchucks in the Cherry and Pear orchards.

I e-mailed Hornady . They said as of now they have no publishable load data for it yet. Any thoughts on where to start?

 

[BALLISTICJESUS]

..

 

[flyinstroke]

I'll be tagging this thread. I didn't even know these existed.

 

[Hoss50]

Anyone? I am looking to land some soon.

 

[QuietTexan]

What all powders do you have to work with?

Trail Boss is safe to start with if you can find any, just be 1000% sure you don't compress it at all. H110, IMR 4727, AA1680 and Lil'Gun are common powders for subsonics. H4895 is know to work well at very low chage densities also.

In terms of hard load data, google-fu says 11.9gn of CFE BLK behind a 245gn lead cast bullet, 10.7gn H110 behind a 220gn Berrys plated bullet.

QL predicts starting around 15.0gn of H110 and working down, should be ~80% fill so you should be able to hear the powder move while shaking the case. If you can't charge lower weights until you can. You should hit subsonic at ~13gn.

 

[ElkSurgeon]

I will also bring up that 7.62x39 is .310 which is what most AK-47 platforms & factory produced bolt rifles are specd to. My Howa 1500 is .310 at least. I'm thinking I would have a hard time stabilizing a .308 SUBX at subsonic speeds especially….

Doesn't mean I am never gonna try it though…….

 

[SubsonicSoviet]

Any updates on this? I just bought a box of factory ammo to get some ideas. I dumped the powder and there was 12gr of some mystery ball powder.

 

[SubsonicSoviet]

Any updates on this? I just bought a box of the factory loaded sub-x in hopes that I could get a better grasp on what they expect us to do or what's working for them. I pulled a bullet and dumped ~12gr of some mystery ball powder. I'm not sure what it is yet, but it's a start.

I made an account on this forum in hopes that someone has any update on the matter. I can't believe they'd release such a heavy for caliber option and not give us any idea how to load it. WILD.

 

[QuietTexan]

I put two types of data up there. What powder do you have to work with for this?

 

[SubsonicSoviet]

I put two types of data up there. What powder do you have to work with for this?

I do have some CFE BLK and 4227, and those might be the only powders that I've got that would be applicable toward this project. I've got a ton of ramshot tac, but it's quite a bit slower than anything mentioned here. I saw hodgdon's data for sub 123gr loads with titegroup, but that was a major bust for me, they were cranking 1400fps out of a 16" RAR rifle.

 

[Dentite]

I will also bring up that 7.62x39 is .310 which is what most AK-47 platforms & factory produced bolt rifles are specd to. My Howa 1500 is .310 at least. I'm thinking I would have a hard time stabilizing a .308 SUBX at subsonic speeds especially….

Doesn't mean I am never gonna try it though…….

I didn't even know these existed until I saw this thread today, but it looks like these are oversized diameter specifically for the 7.62x39 based on what I'm seeing here:

If anyone has used these for subsonic 300blk loads, I'd like to know.

 

[Txbrassman]

I've found that 14.2 grains of CFE Black keeps me subsonic and will cycle the AK with a dead air wolverine attached.
For .300 Black I've used the 255s by running them through a .308 sizing die and then loading them with 9.2 grains of Lil'Gun.