300 AAC Blackout-reloading data

[texag93]

Since some already have them and others will soon, lets put some reloading data in one place. I have nothing proven yet but here's what I've rounded up so far.

[Chad C]

I'll keep an eye on this. I just started accumulating parts for a build.

[texag93]

I loaded a few rounds today. Wouldn't cycle them. I think the subsonic rounds are a little finicky.

[Coach W]

I loaded a few rounds today. Wouldn't cycle them. I think the subsonic rounds are a little finicky.

Subsonic rounds need the back pressure of a suppressor to cycle the action... If you are trying to shoot em un suppressed they won't cycle

[chewy]

you running suppressed on the sub rounds? i have all the stuff to reload but powder and been trying to find h110 around the austin area with no luck.

[bustacap]

Subsonic rounds need the back pressure of a suppressor to cycle the action... If you are trying to shoot em un suppressed they won't cycle

My ar cycles subs without a can. Had a little hiccup with the gas block not in the right place, but now I got it adjusted right.

My brothers ar cycles them too, with no problem.
They really are finicky and need the right amount of pressure.
I've heard of others having to get adjustable gas blocks and drilling a larger hole in the barrel.

[GTXHUNTER88]

we run subs no can off and on getting some custom reloads made in Dallas

[bustacap]

I loaded a few rounds today. Wouldn't cycle them. I think the subsonic rounds are a little finicky.

Did you test any supers to check weapon functionality?

[jaime1982]

Following.

[texag93]

Did you test any supers to check weapon functionality?

Yes. 125 factory run fine. 210 Bergers were iffy. I think another half gain would fix it. They cycled 75% of the time.

I just ordered some bulk bullets. Cant afford to shoot up all my 300 RUM bullets. I'll load super sonic for awhile. It will be a year before I have a suppressor.

[Mike D]

Jason try and find some accurate 1680. It seems to be the most consistent at cycling subs, especially in a carbine length gas system.

[texag93]

Jason try and find some accurate 1680. It seems to be the most consistent at cycling subs, especially in a carbine length gas system.

[ATTACH]476750[/ATTACH]

[ATTACH]476752[/ATTACH]

I tried downloading this ^^^. Wasn't successful. I'll look for 1680. I'm using H4198 now since its the only powder I have that's been listed.

[John Galt]

This is the "Official" recipe from the 300AACBlackout site for the subsonics.

• R-P 300 AAC BLACKOUT brass
• Remington 7.5 primers
• 11.2 grains of A1680 powder (Adjust powder charge down as needed. Factory
ammo is 1010 fps for 16" barrel)
• Case length is 1.368 +0.000 -0.020
• Sierra 220 MK loaded to 2.120 OAL (this length is optimal for reliable
feeding from USGI magazines)
• Chamber pressure 21,100 psi.


I haven't reloaded any yet but have everything I need to start. Except dies.

[texag93]

This is the "Official" recipe from the 300AACBlackout site for the subsonics.

• R-P 300 AAC BLACKOUT brass
• Remington 7.5 primers
• 11.2 grains of A1680 powder (Adjust powder charge down as needed. Factory
ammo is 1010 fps for 16" barrel)
• Case length is 1.368 +0.000 -0.020
• Sierra 220 MK loaded to 2.120 OAL (this length is optimal for reliable
feeding from USGI magazines)
• Chamber pressure 21,100 psi.


I haven't reloaded any yet but have everything I need to start. Except dies.

I have everything but powder and those bullets.

[jrpwa]

That's what I use A1680 seemed to do the trick for me.
Just waiting on the can now.